A suicide bomber exploded his car outside a building housing the government’s department for martyrs and disabled persons before gunmen stormed the building Monday armed with automatic rifles and explosive devises, Kabul police chief spokesman Basir Mujahid said.

Four people have been reported injured in the attack that occurred as workers were preparing to leave for the day, said Mujahid, adding that police were still battling the gunmen. More casualties seemed likely, he said.

Deputy Interior Ministry spokesman Nasrat Rahimi said 200 employees have been evacuated and are safe, but several other employees are hostage to the gunmen. He couldn’t say how many gunmen were involved in the attack, but said police have killed two of them. There were more still inside the building, he said.

Police have cordoned off the area in the east of the capital Kabul as they try to gain control of the situation, The Associated Press reports.

Several apartment buildings as well as a government public works department building are located in the same eastern Kabul neighborhood where the attack is underway. Eyewitnesses reported that a portion of the government building was in flames and several smaller explosions were heard amid the ongoing gunbattle.

No one claimed responsibility but both the Taliban and the local Islamic State affiliate have carried out brazen daytime attacks in the capital.