A Yugoslav army veteran who manned anti-aircraft defenses during the NATO bombing in 1999 tossed a hand grenade into the U.S. embassy compound in Podgorica, capital of Montenegro, around midnight and then blew himself up, police said on Thursday, Reuters reports.

The embassy on its Facebook page said all its personnel were safe after the incident and there were no reports either of material damage.

The Montenegrin man, aged about 41 and born in Serbia, was identified by police only by the initials D.J., though media named him as Dalibor Jaukovic, a decorated Yugoslav army veteran.

“He was a real patriot during the NATO bombing. He served with the Yugoslav anti-aircraft defenses,” Milutin Dragicevic, who described himself as a distant relative told Reuters.

At just before midnight, the man lobbed a hand grenade over the embassy compound fence and then blew himself up, assistant police chief, Enis Bakovic, told reporters.

Bakovic said an investigation was underway to determine whether he had acted alone or with others. “We are searching social media together with the FBI,” he said.

“There are no indications this was an act of terrorism,” prosecutor Lepa Medenica said.