There was no immediate claim of responsibility. The al Qaeda-linked Somali insurgent group al Shabaab has carried out deadly attacks in Uganda. Last month another group, the Islamic State-aligned Allied Democratic Forces (ADF), claimed its first attack in Uganda.

The explosions – one very close to parliament and one near the central police station – sent bloodied office workers scrambling for cover over shards of broken glass as a plume of white smoke rose above the downtown area.

“A booming sound like that from a big gun went off. The ground shook, my ears nearly went deaf,” Peter Olupot, a 28-year-old bank guard who was near the attack, told Reuters. “I saw a vehicle on fire and everyone was running and panicking. I saw a boda boda (motorcycle) man – his head was smashed and covered in blood.”

A Reuters witness saw burned cars behind a police cordon at the scene and a reporter with local television station NTV Uganda said he saw two bodies in the street.

Mulaago Hospital was treating 24 blast victims, four of whom were in critical condition, Emmanuel Ainebyoona, a spokesperson for the health ministry, said on Twitter.

A Ugandan military spokesperson, Brigadier Flavia Byekwaso, told Reuters that there had been “multiple” blasts and “multiple” casualties but declined to give further details.

Irene Nakasiita, spokesperson at the Uganda Red Cross, said they would release information about the blasts later. Uganda’s police did not respond immediately to requests for comment.

Ugandan soldiers are fighting al Shabaab in Somalia as part of an U.N.-backed African Union peacekeeping force. Al Shabaab’s bombings in Uganda include a 2010 attack that killed 70 people watching the World Cup.

Last month, the ADF made its first claim of responsibility for a blast in Uganda with a bomb – packed with shrapnel – that killed a waitress at a restaurant.

Also last month, Ugandan police said a suicide bomber had blown up a bus, killing himself and injuring others. His affiliation was unclear.

The ADF was originally established by Ugandan Muslims but now have their main bases in the forested mountains of the Democratic Republic of Congo, which borders Uganda.

Both the ADF and al Shabaab frequently use explosive devices and have been accused of killing thousands of civilians.

By Elias Biryabarema.

(Reporting by Elias Biryabarema; Editing by Andrew Heavens Writing by Katharine Houreld; Editing by Andrew Heavens and Giles Elgood).