At least one militant on a motorbike blew himself up outside the U.S. embassy in Tunisia on Friday wounding five police, local media reported, in the country's most serious apparent attack since the summer.
Embassy officials confirmed the attack in a tweet on its official Twitter feed, and urged people to avoid the area.
A Reuters reporter saw a scorched, damaged motorbike and a damaged police vehicle a few metres from the embassy's main gate, as a helicopter whirled overhead and large numbers of police gathered.
Radio Mosaique, a local radio station, reported that the attacker had injured five police officers when blowing himself up. The station also reported that there may have been a second perpetrator.
Sirens could be heard on the major highway linking the Lac district, where the embassy is located, with Tunis and suburbs in the north.
Last summer, Islamic State said it was behind three militant blasts in the capital, including one near the French embassy that killed a policeman and another that wounded five people during a security operation to detain a suspect.
Tunisia's critical tourism sector is highly vulnerable to militant incidents and was devastated after two major attacks in 2015, which killed scores of visitors at a beach resort and a popular museum.
Diplomats who have worked with Tunisia on its security capacity say it has grown more effective in preventing and responding to militant attacks in recent years.