Two unrelated armed robberies happened within 45 minutes of each other early Thursday morning.

Shortly before 3 a.m., a drive-through customer robbed the McDonald’s at 1309 W. Sixth St. The robber ordered food, then pulled up to a store window holding a handgun and covering his face, said Sgt. Mike Pattrick, a Lawrence Police spokesman.

The man demanded money from a 16-year-old employee and left with an undisclosed amount of cash, Pattrick said.

Police have no suspects.

In an unrelated case, police in Topeka arrested three 15-year-old suspects in connection with an armed robbery about 2:21 a.m. near the intersection of Harvard Road and Wakarusa Drive.

Four boys, all age 17, told police that while they were walking near the intersection, the three suspects approached them and demanded money. One held them at gunpoint as the two others searched their pockets and took a cell phone.

The suspects fled, but one of the victims gave chase. He grabbed one of the suspects by his shirt, and the suspect turned and punched him in the face, the boys told police.

¢ 6News video: Two armed robberies in Lawrence

The suspects then got into a four-door Honda parked in the 4800 block of Harvard Road, and the group of victims was able to record the license-plate number.

Lawrence Police broadcast a description of the car, and police later arrested the 15-year-olds in Topeka. Two other people who were in the car, an 18- and 19-year-old, were not arrested, Pattrick said.

He said police recovered a handgun from the car but didn’t have a detailed description Thursday.

The suspects were in the Juvenile Detention Center Thursday morning, Pattrick said.