The photo shows an ashtray on a coffee table, just to the left of the corpse, with two bits of soot remaining in it.

But there was only soot, and no cigarette butts.

Lu Chuan had already seen the autopsy report, and the tips of the index and middle fingers of the deceased Zhang Wen's right hand were scorched yellow, with obvious smoke marks, and he obviously had a history of smoking.

It's normal for a smoker to have soot in the ashtray on the coffee table.

The question is, there is soot, why not cigarette butts?

Lu Chuan looked surprised and continued to flip through the photo, and a moment later, a photo of the trash can in front of the deceased's house appeared on the screen.

A cigarette butt is at the bottom of the trash can!

Zoom in on the photo, the logo on the cigarette butt has burned out, and the end of the filter connecting the tobacco has been burned.

Lu Chuan himself smokes, and it is clear that this situation is due to the fact that the smoker did not extinguish the cigarette butt, resulting in the situation after the cigarette butt burned out naturally.

Was this cigarette butt left by the deceased Zhang Wen?

Lu Chuan frowned, and the next time he flipped through the photos, this time he only flipped through a few photos, and a cigarette case appeared on the screen.

Every item on the coffee table, Lu Chuan numbered it and took pictures.

Hongmei brand cigarettes, there is also a lighter next to the cigarette case, which should be the cigarette that Zhang Wen usually smokes.

This cigarette is not expensive, when Lu Chuan was in college, his classmates often bought this kind of cigarette, and Lu Chuan also smoked it.

So I am more familiar with this cigarette.

It is because of familiarity that the problem is discovered.

The filter of Hongmei brand cigarettes is different from the filter of ordinary cigarettes, with light yellow spots distributed.

However, there are no light yellow spots on the cigarette butt filter inside the trash can.

In other words, the cigarette butt that burned out without a brand logo was most likely not smoked by Zhang Wen.

It wasn't Zhang Wen who sucked it, who left it?

A flash of excitement flashed in Lu Chuan's eyes, could it be left by the murderer?

Turning to look at the sleeping Liu Guodong, Lu Chuan decided to wake him up, the cigarette butt was not collected as evidence, so now he needs to go to the scene for a re-investigation.

However, there are regulations on the re-investigation, one person cannot enter the site alone, and the re-investigation work needs to be carried out by at least two people, and a third person is required to witness it.

Of course, rules are dead, people are alive, and in the vast majority of cases, it is the auxiliary police who act as the third witness.

It's like an aged middle-aged man, even if the prostate rebellion can't go into battle, but the fingers are still used after all.

Liu Guodong, who was woken up in a daze, was startled by Lu Chuan's green eyes.

"Clues?"

Lu Chuan nodded excitedly, and his fried hair looked like a messy chicken nest: "The cigarette Zhang Wen smokes is Hongmei, but the cigarette butt in the trash can is not Hongmei cigarette, I feel that there is a problem." ”

After listening to Lu Chuan's explanation, Liu Guodong straightened his waist instantly, and after working for a day, he just couldn't keep up with his physical strength, which didn't mean that he didn't have that thought.

"Let's go, let's go to the scene!"

"Do you want to report to Team Qin?"

"No, let's go to the scene and bring things back first, and after collecting the DNA information on it, the evidence will be conclusive!"

Ginger is still old and spicy, don't do things that you are not sure of.

Liu Guodong and Lu Chuan didn't alarm anyone when they left, Room 1 was still noisy, and Qin Yong's angry roar spread throughout the detachment building.

Of course, no one paid attention to the current survey at this time, and their task was basically completed.

The reason why Liu Guodong didn't go home was, on the one hand, that he was embarrassed to leave Lu Chuan here alone.

On the other hand, the case was not solved after all, and he left directly, which was disrespectful and provocative to Captain Qin Yong.

How can the old rivers and lakes do such a thing.

Looking at Lu Chuan, who was full of energy and had green eyes in his eyes, Liu Guodong seemed to have returned to the time when he first joined the company twenty years ago.

"It's nice to be young......"

An hour later.

Next to the DNA detector, Liu Guodong just stared at Lu Chuan's hand operating the instrument: "How is it?" ”

Call!

Lu Chuan took the comparison report and let out a long breath: "The DNA information on the cigarette butt has been determined not to be Zhang Wen's. ”

Dry!

Liu Guodong took the report excitedly and patted Lu Chuan on the shoulder: "Well done!" ”

"You've done a great job...... Well? ”

Liu Guodong's excited expression gradually solidified, and then turned incredible: "This DNA match ......"

Lu Chuan shook his head: "That's right, the DNA information on the cigarette butt is indeed not Zhang Wen's, but it is ...... with him."

"The cigarette butt was left by his son."

Grass!

5:20 a.m.

Twenty-six hours have passed since Zhang Wen's death, and there are still no clues about the breakthrough in the case in Conference Room No. 1.

As the head of the criminal investigation detachment, Qin Yong has come from a front-line criminal police step by step to today, and there have been no less than 20 homicides.

Although the vast majority of these cases have been solved, no one can guarantee that a murder case will be solved.

As for the murder of Zhang Wen, so far, no valuable clues have been found.

Generally speaking, there is a saying that there are 72 golden hours to solve a homicide case, that is, within three days after the crime, the hope of solving the case is the greatest.

It's not that the case can't be solved after this time, but it takes more effort and time.

"Everyone, conduct a comprehensive survey of the vicinity of Zhang Wen's house, every household cannot miss it, and all the visits and investigations are in place."

"The scope of surveillance should also be expanded, and the surveillance videos of all intersections and shops within one kilometer of Zhang Wen's home have been touched!"

In the absence of any clues, the crowd tactic is the best weapon for the criminal police to solve the case.

This is also one of the reasons for the golden seventy-two hours, and the three-day battle of the crowd tactics is the limit of ordinary people.

Bang!

The door to Conference Room 1 was violently pushed open, and all eyes were on the door.

At this time, if you dare to enter the No. 1 conference room, everyone wants to see who it is.

Qin Yong's attention was also attracted, and he found that it was Liu Guodong from the current investigation office, and his gloomy face was slightly gloomy.

Liu Guodong is an old qualification, and he joined the police at the same time as Qin Yong, although he has no official position now, but he leads the current survey, which can be regarded as the technical backbone of the detachment.

Qin Yong looked at the time, it was almost six o'clock in the morning: "Lao Liu, why haven't you gone back to rest, you've been busy with surveys during the day, you ......"

Liu Guodong shook his head and directly interrupted Qin Yong's words: "Team Qin, there are clues!" ”

There are clues!

Qin Yongteng bounced up from his seat, his tired eyes flashing with a fierce light: "Have you found anything now?" ”

Liu Guodong nodded heavily, and handed Zhang Wen and the DNA information comparison report collected on the cigarette butts in the trash can to Qin Yong: "The cigarette butts in Zhang Wen's house are not the deceased, but his son's!" ”

His son's?

Ecstasy flashed in Qin Yong's heart!

Zhang Wen's son Zhang Minlu does not usually live with Zhang Wen.

Yesterday morning, Zhang Minlu went to pick up Zhang Wen for a physical examination, and reported the case only when he found that Zhang Wen had died.

Since the two don't live together, how could Zhang Wen's family have cigarette butts that Zhang Minlu smoked?

Could it be that this guy smoked a cigarette when he reported the crime after seeing his father die?

"Lao Liu, the case has been solved, and you are the first to invest!"

"One group and two groups, immediately follow me and go to Zhang Minlu's house!"