The U.S. Embassy in Tunis, the capital of Tunisia, said Friday that emergency crews are responding to an explosion near its building in the city.

Unconfirmed local media reports said a suspected suicide bomber blew himself up after detonating a bomb. An individual riding a bike detonated the device near the police patrol opposite the embassy, reports said. Local reports said five police officers were wounded.

Crowds were seen in pictures on social media gathering outside the embassy. The flag of the United States could be seen fluttering in the background.

The private Radio Mosaique said that five police officers were wounded in the explosion Friday. That report could not be immediately confirmed.

Islamic extremists have targeted Tunisia in recent years, killing scores of people.

The Associated Press contributed to this report