Philadelphia police say they've apprehended the teenage robbers responsible for two stickups at South Philadelphia corner stores and an attempted holdup at another.

Officials said the pair was identified through tips and have turned themselves into police to face charges.

The names of the suspects, both 16-year-old males, were not released because they are juveniles.

The first incident occurred on Dec. 23, when the pair robbed Susan's Grocery, at 1501 S. 13th St., at about 6:45 p.m., police said.

One of the suspects pointed a handgun at a 74-year-old female worker who was sweeping the floor and demanded money, authorities said.

The suspect then tossed a backpack at another employee, a 32-year-old man, who opened the cash register and put money inside the backpack. The duo then fled the scene on foot, having made off with about $500 in cash.

On Christmas Day, a teenager tried to rob Joe's Food Mart II, at 1900 E. Passyunk Ave., at gunpoint at about 2:20 p.m., police said. But when the 39-year-old male employee refused to put cash in the assailant's backpack and reached under the store counter, the robber fled empty-handed.

A few hours later, police said, the pair tried to order sandwiches at New Matt's Market, at 1427 S. 6th St., as the business was closing about 8:15 p.m.

The two left the store, then returned about 15 minutes later, brandished a handgun and demanded money, police said. A 50-year-old male worker put $300 in cash in a white plastic bag, and the duo fled.

Police said the suspects are facing charges that include robbery, aggravated assault and criminal conspiracy.