Unidentified gunmen opened fire at a police barricade outside the US embassy in Sana'a on Monday, but there were no reports of casualties, a police source said.
The source told Deutsche Presse-Agentur dpa that the attackers fled in a car after firing several shots at a checkpoint on a street leading to the embassy.
The car was found on a neighbouring street minutes later, and three suspects were arrested, the source said.