PHILADELPHIA (CBS) – For the second time in as many days, a thief has targeted a convent in Philadelphia.

Police say someone broke into the nun convent at the St. Gabriel Parish in Grays Ferry early Thursday morning. The alarms went off inside the building, but investigators say nothing was stolen.

However, that was not the case only 24 hours earlier.

An intruder entered the convent through a front window at about 2 a.m. Wednesday, stealing $150 in cash — money the nuns were using to buy their food and to help conduct classes at the parish grade school.

Sister Marian Gregory, the house superior for the 11 sisters of the Immaculate Heart of Mary, says the convent alarm sounded twice during the night Wednesday, but sisters who investigated the activation did not come face to face with the intruder.

Detectives spent Wednesday and Thursday looking for possible evidence, including fingerprints they hope could lead to the suspect.

St. Gabriel Parish has been part of the Grays Ferry community for more than a century. Crime has forced the sisters to cover some of their windows with iron bars.

The community has vowed to work together to restore the stolen money to the sisters.

Anyone with information about either burglary is asked to call South Detectives Division at 215-686-3013.