An attacker threw a hand grenade at the US embassy in Montenegro's capital and then killed himself with another explosive device, the government here said Thursday.
No one else was hurt and there was no major damage. Police sealed off the area after the blasts around midnight (3am Thursday, UAE time).
The US State Department said embassy officials were working with police to identify the assailant and was working internally to confirm all staff are safe.
Montenegro borders the Adriatic Sea in southeastern Europe and its capital is Podgorica. It joined Nato last year despite strong opposition from its traditional Slavic ally Russia.
Several people, including two Russian secret service operatives, are on trial in Podgorica on charges that they wanted to overthrow Montenegro's government in 2016 because of its pro-Western policies.
The US established diplomatic ties with the tiny Balkan state in 2006 after it split from much larger Serbia.
A US State Department spokesperson confirmed "a small explosion near the US Embassy compound", adding that "at this time Embassy officials are working closely with police to identify the assailant(s)".
The embassy said on its Twitter account that it had cancelled all visa services for Thursday, adding that access for US citizens "will be available today on an emergency basis".
A guard near the scene who asked not to be named said he "heard two explosions, one after another".
"Police came very quickly and the body of a man was taken away," the witness told AFP.