Updated

Two gunmen have been killed and 10 hostages have been rescued after a hostage situation unfolded in the Somali capital of Mogadishu Wednesday, following reports of a car bomb, police said.

An unknown number of hostages were being held by gunmen posing as military forces inside of the Pizza House restaurant, a popular eatery in the Somali capital.

Five attackers are thought to remain in the restaurant, according to Capt. Mohamed Hussein.

Before the hostage situation, an explosive-laden vehicle exploded at the restaurant’s gate, killing at least 17 people and wounding several others, police said.

Initial reports claimed gunmen rushed inside the restaurant soon after the explosion.

Most of the victims were young men who were entering the Pizza House at the time, Hussein said.

Al-Shabab, a Somalia-based extremist group that often targets popular areas in Mogadishu, claimed responsibility and says their attack is ongoing.

“A mujahid (fighter) with his suicide car bomb martyred himself after he rammed into Posh Hotel, which is a nightclub. The operation goes on,” Abdiasis Abu Musab, the group’s military spokesman, told Reuters.

The group has vowed to step up attacks after the recently elected government launched a new military offensive against it.

Abas Ahmed, who was at a nearby restaurant when the explosion happened, told i24News that he saw "the dead bodies of several people and others who were injured."

Wednesday's explosion was the second suicide car bomb outside an eatery in Mogadishu in two months. In early May, 8 people were killed when a car bomb exploded outside Bar Italia. Al-Shabab claimed responsibility.

Al-Shabab last year became the deadliest Islamic extremist group in Africa, with more than 4,200 people killed in 2016, according to the Washington-based Africa Center for Strategic Studies.

The extremist group also faces a new military push from the United States after President Donald Trump approved expanded operations, including airstrikes, against al-Shabab. On Sunday, the U.S. military in Africa said it carried out an airstrike in southern Somalia that killed eight Islamic extremists at a rebel command and logistics camp.

The Associated Press contributed to this report.