VIENNA — Police say an Austrian attacker was shot and killed by the guard he wounded outside the Iranian ambassador’s residence in Vienna.

Police spokesman Harald Soros said the guard was wounded in the arm before he shot the attacker dead shortly before midnight Sunday.

The spokesman said the attacker was a 26-year-old Austrian man. The motive for the attack was not clear.

Police ordered reinforcements around all diplomatic missions in the Austrian capital, which is also home to many international organizations.