PHILADELPHIA (CBS) -- Top law enforcement officials and politicians are speaking out one week after Officer Jesse Hartnett was gunned down.
FBI officials told CBS News while investigators have not concluded the Jan. 7 shooting was an act of terrorism, the shooting is being handled as a terrorism investigation.
James Comey, the director of the FBI, held a press conference Thursday afternoon. He says, so far, there is no proof the suspect is part of a larger cell, and there is no indication of any follow-on plot or credible threat of violence, but the investigation continues.
Comey said, "We at the FBI level, we are investigating the attack as a terrorist attack."
Only CBS 3 was at Penn Presbyterian Hospital Thursday morning, where Officer Hartnett is recovering from three bullet wounds to his arm, as the FBI director and police commissioner Richard Ross both went into the hospital to pay a ten minute visit to the wounded officer.
Officer Hartnett remains in the Intensive Care Unit.
It was late last Thursday night that Officer Hartnett was gunned down at 60th and Spruce Streets in West Philadelphia in what police are calling an ambush attack.
The suspect, Edward Archer, was arrested and allegedly confessed, saying that his motives were related to the Islamic State.
It has prompted a lot of controversy and a lot of investigating in the wake of the shooting, including questions about whether Archer had links to anyone else, or whether any other attacks might be planned.
Philadelphia Police are doubling up in two man police cars for the time being.
Senator Pat Toomey says, "It is appalling. The attack is a vivid reminder of the dangers that the men and women who wear the police uniforms around the country face on a daily basis. Radical Islamic terrorism is not limited to countries far away. It is not just civil wars that are raging in the Middle East, or attacks against civilians in Paris, Beirut, Jakarta, but attacks against Americans at Fort Hood and San Bernardino and now Philadelphia."
At a press conference, Mayor Jim Kenney said, "I don't think speculation is effective. We have to wait and see what the FBI and Philadelphia Police Department discover. Then we will make a determination based on facts. I think speculation has made this thing run wild, scaring people and putting people at risk. I have confidence in the FBI and our police department working together to determine the actual reasons for this. In the meantime, we are concerned for Officer Hartnett and his family and the rest of the police to make sure they are safe."
"The 200,000 Muslims who live in Philadelphia are not represented by the actions of Mr. Archer. He is a criminal and they are not criminals. I think it is important that we make very clear that regardless of where this leads that those folks, who are God-fearing, tax paying Americans, should not be painted with that broad brush. I think it is important that we highlight that."
Mayor Kenney added, "Was I misinterpreted by Republicans? Yes, I think it's pretty easy for them to do. They misinterpret a lot of things. The FBI and police have not concluded that this is an act of terrorism. They are investigating it as it could be, but I think our FBI and police know more than Rush Limbaugh."
Senator Bob Casey said, "When we see what happened in Philadelphia and we see what happened in Harrisburg with the arrest of a 19 year old by the FBI, and what happened in San Bernardino, we're seeing the rise of a lone wolf problem."
Last weekend, an anonymous informant told Philadelphia police that the danger was not over and that there were at least three other suspects, potentially more dangerous, who may be involved. The investigation is ongoing, but sources tell CBS 3 so far there is no link beyond Archer to anyone else.
Commissioner Ross says, "Part of the problem is we haven't gotten a lot of movement, we still are with Archer. We haven't linked him to anyone else right now. We know that tip that was given was somewhat credible, but still no link to other individuals other than identifying people he may know."
Archer remains behind bars without bail.
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