The thefts happened on July 1 at the following locations in under two hours:
-4300-block of North Milwaukee Avenue between 4:05 and 4:20 p.m.
-6300-block of West Strong Street at 4:21 p.m.
-900-block of South Mayfield Avenue at 5:45 p.m.
RELATED | Thieves steal mail from 3 USPS trucks within 2 hours on Northwest, West sides: Chicago police
The U.S. Postal Inspection Service calls these crimes of opportunity, as the carriers were out of their vehicles delivering mail at the time.
The new video shows a white SUV follow a USPS vehicle.
Once the worker leaves their truck, two men break the passenger window and steal mail and packages, according to police.
Thieves caught on camera following, stealing from USPS trucks | FULL VIDEO
A reward of up to $150,000 is being offered for information leading to the arrest of another suspect for her role in the June 28 armed robbery of a USPS worker.
The incident took place near 5050 S. Evans Ave. in Bronzeville.
Video shows a woman wearing a pink hair bonnet approach the postal worker, who is seen backing away, as she appears to flash a weapon.
The postal worker was not injured.
Police say the suspect is armed and dangerous.
One man who lives in the area said these robberies are becoming too common.
"Man, it's not good. It's not good, can't be like that," Larry Williams said.
Anyone with information is asked to call 877-876-2455.
The Postal Workers Union said the robberies have been going on for years, no matter what they do.
The United States Postal Inspection Service is seeking more help from elected officials to stop the ongoing armed robberies.
"It still goes to show we're still under attack, and anyone can just walk up to us. And this is what we have to deal with," said Elise Foster, with Branch 11 of the National Association of Letter Carriers.
Foster said she's been in contact with local and federal officials to get more help.
"My members are scared. They don't know day to day if they're gonna make it home to their families, and that should not be on their mind," Foster said. "I can't say it's getting better because we're still having these conversations, and we get random attacks on the letter carriers: One is one too many."
As the postal service looks into additional security measures, Foster said they've already implemented a notification system internally to try and keep the letter carriers safe while on their routes.
"We can touch down to those carriers that opt in to let them know what's going on, so they can be aware of their surroundings, let them know, 'hey, your brothers and sisters just got attacked on the next block. Be careful because they may be on their way to you," Foster said.
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