A marijuana delivery driver was beaten and robbed at gunpoint Tuesday night when he made a delivery to an apartment complex in Portland, police said.

The robbery and two similar incidents in October highlight the risk to delivery drivers in Maine’s expanding marijuana industry, police said.

The driver was working for an unidentified medical marijuana delivery business Tuesday, and when he arrived at an address at the Wellesley Estates complex after 8:30 p.m., he was approached by two men who pointed handguns at the driver.

The men approached from either side of the vehicle demanding cash. When the driver said he didn’t have any, one of the men struck the driver with the handgun, searched the victim’s pockets and stole a wallet and cash from previous deliveries. At the same time, the other suspect searched the vehicle and stole a backpack containing marijuana, cannabis products and personal belongings.

Both suspects were seen fleeing toward the Riverton Park housing complex.

Two similar incidents occurred in October, police said, and in all three cases, the suspects used phone apps to order the marijuana and provide driver’s licenses and medical marijuana cards. In all cases, the medical marijuana cards were stolen, and in two of the three cases, the address provided was not a valid address.

The presence of marijuana and cash make delivery drivers robbery targets, said Portland police Chief Frank Clark. He urged drivers not to resist during the robberies for fear someone may be seriously hurt.

“Portland Police will continue to work with lawfully operating delivery companies to address their safety concerns,” Clark said in a statement. “We urge drivers to not resist during these crimes. They should minimize the amount of cash and cannabis products they have on hand and try to meet with potential customers in public locations.”

The earlier two robberies were in October. The first, on Oct. 8, took place around 8:30 p.m. on Auburn Street. The delivery person was on foot looking for an address when he was approached by a young-looking man who grabbed the  bag of marijuana and fled.

The second case, Oct. 25, occurred on Danforth Street. The delivery driver had not yet exited the vehicle when two people in their early 20s who were sitting on some steps nearby approached the vehicle. While one person assaulted the driver, the other person tried to steal a bag of marijuana, police said. Then the two subjects switched roles, with the first trying to find marijuana, while the second person assaulted the driver.