When Texas-based MetroPCS Communications Inc. announced plans in July to launch stores in Philadelphia, the company touted its "affordable, worry-free" wireless services.

The company apparently failed to mention a more dubious store feature: Easy-to-rob.

Citing a lack of security and quick access to cash, police say robbers hit 10 MetroPCS stores citywide on 12 occasions over a 29-day period.

MetroPCS sells cell phones and flat-rate wireless service plans that don't require a contract, according to the company's Web site, and bill payments can be made at stores.

"Unfortunately, the way these stores are set up, the accessibility to the safe is very easy," Police Chief Inspector William Colarulo said at a news conference yesterday.

In each incident, the suspects first cased the store, then concealed their faces using hoodies or bandanas. They barged in, put a gun or knife to employees' heads and ordered them to open the safe, Colarulo said.

From Nov. 29 through Dec. 27, the suspects struck 12 times, stealing as much as $5,000 from a MetroPCS store in the city's Strawberry Mansion section on Dec. 8. All told, the suspects made off with about $17,000 in cash. In at least one robbery, the suspects terrorized store employees with a large machete, Colarulo said.

Police yesterday released video-surveillance tapes from the stores. In one tape, a female clerk at a Kensington store is seen cowering in the corner, seemingly crying, as a suspect wields a knife at her on Dec. 20 at 11:45 a.m.

"As you can see, it's a very violent robbery," Colarulo said. "It's just amazing that there were no injuries inside the store."

Colarulo said police caught a major break in the spree on Saturday when two cops from the 25th Police District in North Philly - Officers Sylvester White and James Morrison - quickly responded to a robbery at the MetroPCS store in Juniata Park.

Based on a description given by store employees, White and Morrison arrested the suspects after stopping a car less than three miles from the store, Colarulo said.

Police did not release further details, saying they believe other suspects are involved and they are working on potential leads.

MetroPCS Communications Inc. did not immediately return calls to its Dallas headquarters from the Daily News yesterday.

Police asked anyone with information about the PCS robberies to call the Major Crimes Unit at 215-686-3396 or 215-686-3397. *