AURORA -- The Aurora Police Department is seeking assistance from the public to identify the men responsible for up to 10 armed robberies of Hispanic businesses in Aurora since March 11.

The reward for information to men's arrest has been increased to $2,000, Detective Shannon Lucy announced Monday. Police first alerted the public to the serial robberies on March 24. Police reported five similar robberies at that time, but the number has now doubled, with one business being hit twice, Lucy said.

During the initial robberies, the bandits often wore "Jason"-type hockey masks to disguise themselves.

"They now tend to use bandannas to conceal their faces, as well as wearing hoodies," Lucy said.

"I was so scared," said Ana Luna, a waitress at El Conelo restaurant on East Mississippi Avenue.

Luna said when the masked gunman entered her restaurant, he began shouting in Spanish at people in the restaurant.

"He said, 'Everybody on the floor,'" Luna told 7NEWS.

"He asked me for the money," Luna explained. She said she opened the register, gave the robber cash, and he left.

"Not only are they pointing guns at people, but they're very brazen. They're going into these businesses when there are customers there," Lucy said.

According to police, the first man was described as Hispanic, about 5 feet 10 inches to 6 feet tall, with medium to heavy build, possibly in his 20s.

The second man was also Hispanic, 5 feet 7 inches to 5 feet 8 inches tall. He has a skinny to medium build, and is also possibly in his 20s.

Detectives believe that the two initial suspect descriptions remain accurate, but now believe there may be more people involved in the robberies.

Investigators released a composite image of one of the possible suspects and said the suspects may be associated with a newer model silver, mid-size, four-door sedan.

The only injury reported during the robberies was when a restaurant owner was punched in the face by one of the robbers. That incident was caught on tape and aired on 7NEWS on March 24.

Lucy said Monday police are concerned that the violence could escalate.

Aurora police provided the following list of robbery locations believed to be connected to the same suspects.

March 11 -- Taco Y Salsa, 2248 S. Chambers Road
March 16 -- Los Toritos Restaurant, 304 S. Havana Street
March 18 -- Tortas Y Tacos, 796 N. Peoria Street
March 20 -- Guadalajara Restaurant, 1001 S. Abilene Street
March 21 -- Carniceria Dariana, 12028 E. Mississippi Avenue
April 4 -- El Rancho Market, 15401 E. Mississippi Avenue
April 30 -- El Canelo Restaurant, 12507 E. Mississippi Avenue
May 8 -- Carniceria Dariana, 12028 E. Mississippi Avenue
May 9 -- Senor Rics, 13200 E. Mississippi Avenue
May 9 -- El Camarron Loco Restaurant, 513 N. Havana Street

Anyone with information is asked to call Detective Rick Day at 303-739-1835.