Police investigating the apparent car attack at Beijing's Forbidden City searched Tuesday for information on two ethnic Uighur minority suspects, a hotel employee said, a day after the vehicle plowed through a crowd and crashed, killing five people and injuring 38.

Police released no public information about a possible motive for the incident at one of China's most politically sensitive and heavily guarded public spaces, and it was not immediately clear if the two suspects were among the three people killed inside the vehicle.

Two bystanders, including a Filipino woman, also were killed when the sport utility vehicle veered inside of a barrier separating a crowded sidewalk from a busy avenue and then drove toward Tiananmen Gate, which stands opposite the sprawling Tiananmen Square.

Any incident in the area is sensitive because the square was the focus of a 1989 pro-democracy movement that was violently suppressed by the military.

The 38 injured were among the crowds in front of the gate, where a large portrait of Mao Zedong hangs near the southern entrance to the former imperial palace. Three other Filipinos and a Japanese man were among the injured, police said, but there were no immediate details on their conditions.

Zhao Fuzhou, a security official at Beijing's Xinjiang Dasha hotel, said police had circulated a notice searching for information about two suspects with Uighur names in the aftermath of Monday's deaths. Unconfirmed copies of the notice also were widely circulated on the Chinese internet.

One of the men, identified in the notice as Yusupu Wumaierniyazi, was listed as living at the address of a town in Xinjiang in which 24 police and civilians and 13 militants were killed in an attack on June 26.

Radicals among the Muslim Turkic Uighurs have been fighting a low-intensity insurgency against Chinese rule for years. This summer saw an unusually large number of violent incidents and Chinese security forces say they have been guarding against attacks outside of Xinjiang.

Uighurs are culturally, religiously and linguistically distinct from China's ethnic Han majority and many have chafed under heavy-handed Communist Party rule.

Beijing police said on their microblog that they were taking "effective measures to ensure the capital's safety and stability."