Police converged on a Green Tree home Tuesday where they believed someone may have been inside with firearms, explosives and as many as seven hostages, only to find the home was empty and its owner was on vacation.

Green Tree police Lt. Chad Rannigan said police received a 911 call about 11:30 a.m. from a man with a foreign accent who said he was holding hostages at 1118 Greentree Road. He said the man was demanding a ransom or he would begin shooting hostages.

After surveying the home, setting up a command post at a nearby church and blocking traffic into the area, Allegheny County police deployed a robot and found no sign of anyone inside.

About 2:30 p.m., officers with the Critical Incident Response Team then entered and verified the house was empty, said Green Tree police Chief Andrew Lisiecki. The response team is organized by the South Hills Area Council of Governments.

Authorities were able to make contact with the home's owner, a male who was out of state and confirmed that no one should have been inside his house.

Perhaps the most confounding element of the incident is that the call came in on what Lt. Rannigan called a "nonrecorded line," meaning police could not determine the call's origin or location or who was on the line. The call came in to a Pittsburgh dispatch center, which relayed the information to Green Tree.

He said such circumstances were "unusual" and that police were not yet labeling the call a hoax, but rather describing it as a "bad call with bad information."

"I just hope it wasn't a bad address and someone really did need help," he said.

Because police cannot determine the caller's location or identity, the investigation, as it stands, cannot go very far.

Early reports suggested that the situation might have been related to a robbery in nearby Crafton earlier in the day, but Lt. Rannigan said police had no reason to suspect there was a connection.

The Green Tree public works trucks blocking motorists from proceeding toward the scene remained in place until about 4 p.m. Police from Crafton, Mt. Lebanon, Ingram, Scott and Pleasant Hills plus state police and the Allegheny County Bomb Squad were also at the scene.