The staff on duty retrieved the curve.

From 6 pm to 10 pm last night, the relevant curve did not fluctuate at all; it was a completely long line.

Several people frowned slightly.

The staff on duty said, "It shouldn't be this time period. Should I adjust it downwards?"

Zhao Dong nodded and said, "Go ahead and do it."

The staff on duty adjusted the hours to 10:00 AM to 2:00 AM yesterday.

The same straight, long lines.

Similar things continue to happen.

......

From 4 a.m. to 8 a.m.

When the image was brought up, everyone's expression changed.

Because there is a noticeable small valley in the middle section.

Zhao Dong pointed to the valley floor and frowned, asking, "What time period is this?"

The staff member on duty zoomed out the screen and showed the specific time range, saying, "From 5:20 AM to 6:03 AM!"

6:03?

That should be the time it takes for the patrol officers to handle the situation on site.

Zhao Dong stared at the curve and said, "Can you zoom in a bit more? I need to confirm the final pressure data."

The staff on duty zoomed in on the relevant details again.

Zhao Dong then observed the pressure decrease from a steady 0.53 MPa to 0.48 MPa.

As expected, this period is when the gas leak will occur.

He asked, "Is this a common occurrence?"

The staff member on duty shook his head and said, "It's not common! Our gas storage tanks are all sealed devices, and it's rare for the gas pressure to drop suddenly. In general, we would investigate this situation now. However, this drop is not enough. If it drops to around 0.45 MPa, an alarm will be triggered, and we will notice it."

"Is it accurate? What you mean by calling the police?"

Zhao Dong couldn't help but ask, because it was related to the subsequent judgment.

The staff member on duty said, "It's accurate. It will pop up a window and issue a red alarm signal, which we can observe immediately."

Zhao Dong nodded and said, "I understand! Please wait a moment while I take the photos."

The staff on duty stepped aside.

After taking the photo, Zhao Dong looked at the officer on duty and reminded him, "The case is under investigation. Don't tell anyone about this. If we solve the case, your performance just now will be considered meritorious, and we will give you a reward!"

"But if you leak information and alert criminals, then you will bear certain criminal responsibility! Do you understand what I mean?"

The staff member on duty nodded hurriedly and said, "I understand!"

Director Zhang also chimed in, "Xiao Yang, I called you over because I know you're good with your mouth. Don't tell anyone else, or I'll be in trouble, and you'll be in trouble too!"

The staff on duty repeatedly assured them.

Zhao Dong walked to the side and dialed Guan Feng's number: "Xiao Guan, the method you just told me is very useful. I have found a clue."

Guan Feng asked in surprise, "So fast?"

Zhao Dong said, "After listening to what you said, I came to the central control room here immediately and actually retrieved some data."

Guan Feng asked, "Has the specific time been set?"

Zhao Dong said, "It's confirmed! The normal pressure of this gas tank is around 0.53 MPa. Between 5:20 and 6:03 this morning, the pressure dropped to around 0.48 MPa."

Guan Feng frowned and said, "Then the timing isn't a perfect match?"

Zhao Dong said, "Yes, this time is about the same as when the patrolman discovered it. The other party most likely opened the valve around 5:20."

Guan Feng said, "In that case, I'll review the surveillance footage again. Captain, if you have any issues, please let me know so I can adjust the observation period."

Zhao Dong said, "Okay! But Xiao Guan, there's one more thing I need to tell you. The staff on duty said that an alarm will be triggered when the pressure drops to 0.45 MPa, and their people will see it too. Think about the details."

A possibility popped into Guan Feng's mind.

Zhao Dong continued, "You'd better hand over the surveillance to Sheng Guo and the others. Come over here."

Guan Feng asked, "Captain, are you afraid?"

Zhao Dong nodded and said, "Yes! I want to confirm whether these internal personnel are suspects! We'll finalize the investigation of external personnel. Putting everything else aside, if they could bypass surveillance, do you think it was an outsider who committed the crime?"

Guan Feng said, "Dacheng just passed the municipal-level expert assessment..."

Zhao Dong said, "I know what you mean, and I know you want to train him! But the two are not contradictory. If you come here to oversee things, you can also correct some of his problems in time. I'm worried that the suspect is right next to us and we haven't noticed him."

Seeing that the detachment leader had said so, Guan Feng naturally had no further questions and replied, "Alright! I'll go right now!"

After hanging up the phone, he instructed Liu Shengguo and Huang Lili: "The branch captain has found a clue. The valve was most likely opened between 5:20 and 6:03 this morning. You guys focus on reviewing the surveillance footage from that time! I need to go to the office building."

Liu Shengguo said, "Captain, you go ahead and get busy. I'll handle things here."

Guan Feng nodded.

The good thing about Shengguo is that they don't talk much but get things done.

We can't let honest people suffer!

He advised, "You should take some time to study micro-expression analysis, and try to pass the exam in another two or three months."

Liu Shengguo said, "Okay, I'll be the captain. My skill level isn't as good as Dacheng's, and my mind isn't as quick as his, so I'm afraid I can't be that fast, but I will study hard."

Guan Feng said, "Just put in your best effort."

Liu Shengguo said, "I understand!"

Guan Feng patted Liu Shengguo on the shoulder and then walked out of the monitoring room.

He arrived at the office.

Zhao Dong, Gao Dacheng, and others have returned to the office.

Guan Feng pushed open the door and went in.

"Xiao Guan, you're here?"

"The captain is here?"

Guan Feng nodded to Zhao Dong, then said to Gao Dacheng, "Dacheng, continue with your questioning! I came here to check the ledgers; have you obtained them all?"

"Take it, take it!"

Zheng Hua handed over the maintenance logbook.

Guan Feng took the relevant ledgers and then sat down on the side of the long table, where he could see Gao Dacheng on one side and Director Zhang's expression on the other. Seeing that Gao Dacheng was still staring at him, he said, "What are you standing there for? Ask whatever you need to ask! Don't mind me!"

Gao Dacheng said, "Okay! Then I'll ask the captain."

Guan Feng nodded, looking down at the ledger to confirm the records, occasionally glancing up at the expressions of the two men to make sure he hadn't missed any key information.

As Zhao Dong walked in with Guan Feng, he couldn't help but feel more confident.