A series of explosions ripped through downtown Jakarta, Indonesia, on Thursday morning, with reports of gunfire and at least four dead at the time of publication, according to The New York Times.

The midmorning blasts occurred in a number of locations throughout Indonesia's capital. One explosion on Thursday was reported outside the Sarinah shopping center. Another reportedly occurred near a Starbucks cafe. No indications were readily available as to whom or what group was behind the attack. Police officials initially suspected at least one of the explosions was from a suicide bomber, however, The New York Times later reported that no suicide bombers were involved in the attack:

"Gen. Anton Charliyan, a spokesman for the Indonesian National Police, said the attack involved an unknown number of assailants with grenades and guns, at least one of whom was on a motorcycle. He said no suicide bombers were involved. Three civilians and a police officer were killed, he said."

Graphic photos, apparently from the scene, surfaced on Twitter show dead bodies strewn across the street. (Warning: Graphic content.)

"The Starbucks cafe windows are blown out," a Reuters photographer said. "I see three dead people on the road. There has been a lull in the shooting, but someone is on the roof of the building and police are aiming their guns at him."

Indonesia, which claims the world's largest Muslim population, has been hit by terrorist attacks before, and in December, the country's intelligence chief and former governor of Jakarta, Sutiyoso, warned of the terror threat posed by groups such as the so-called Islamic State.

Jeremy Douglas, an official at a United Nations location in Indonesia — which is located near the Sarinah shopping mall — was posting on Twitter as the attack unfolded.

Douglas tweeted that others in the UN office voiced concern that the attack might share similarities with the recent attacks in Paris, which involved foreign militants with links to the Islamic State. He noted the presence of some Indonesians suspected of fighting alongside the militant group.

No group has claimed responsibility for the attack. 

Earlier in January, security forces announced a manhunt for a militant leader called Santoso, who pledged loyalty to the Islamic State, and police arrested suspected IS sympathizers, according to the Atlantic. In December, Australia's attorney general said that he had "no doubt at all" that the extremist group was seeking to establish a "distant caliphate" in Indonesia, the Guardian reported. 

Check back for more on this developing story.

Editor's update, January 13: This story is developing and has been updated to reflect updated information regarding reports of suicide bomber involvement, death toll, and the attack's relation to the Starbucks.