Almost 60 people have been killed and over 100 injured after unidentified gunmen stormed a police training center in the city of Quetta, Pakistan, taking hundreds of cadets hostage. Islamic State terrorist group reportedly claimed responsibility for the attack.

At least 59 people including security personnel have been killed in the standoff, according to health officials cited by Reuters. Pakistani military commandos have managed to rescue over 200 hostages, according to local media reports.

Blood bath in #Quetta , death toll from Islamist attack at police training center rises to over 50 ,over 100 injured #Balochistan — Karachi_Post (@Karachi_Post) October 24, 2016

"Forty eight bodies have been brought to the hospital," Wasim Beg, senior doctor at Quetta's Civil Hospital told Reuters earlier.

At least 3 of the gunmen have also been killed, authorities confirmed. Police and security forces are at the scene and cordoned off the area.

At least two terrorists have reportedly been killed at #Quetta police training college https://t.co/UpBIWfyCd2pic.twitter.com/agylni9AHi — Dawn.com (@dawn_com) October 24, 2016

A major special forces operation lasted for hours after at least five attackers entered the building and opened fire in Balochistan’s capital Quetta late Monday night. Some of the cadets evacuated from Balochistan Police College as special forces arrived to take out the militants.

"Five to six terrorists barged into the academy from [the] back side," the Pakistani media cited the regional government spokesman Anwar ul-Haq Kakar as saying. The attackers then "went straight to the hostel" of the academy, where around 200 to 250 police recruits are normally housed, Kakar said.

As the standoff continued, gunfire and explosions were reported at the scene. Local reports indicate that over 100 people were wounded in the battle, with injured being brought to the Civil Hospital Quetta and CMH hospital.

According to various estimates from 200 to 500 cadets could have been inside the facility at the time of the attack. Generally, cadets studying at the academy are between the ages of 18 and 26, Pakistan-based reporter Javed Rana told RT.

#Quetta under attack.5-6 militants have taken around 200-500 police cadets hostage inside police training center. #Pakistan#Balochistan — Karachi_Post (@Karachi_Post) October 24, 2016

Citing a survivor who escaped the attack, Pakistani Dunya News reported that the attackers opened fire as they stormed the training facility from the rear. Some of the terrorists were wearing suicide vests, the TV channel reported, citing a source close to law enforcement.

Pakistan's Interior Ministry has established a control room to monitor the situation, Dunya News said.

Hundreds of cadets held hostage as 5 to 6 gunmen stormed police training center in #Quetta#Pakistan reports pic.twitter.com/uQLieUTAV2 — Sabena Siddiqi (@sabena_siddiqi) October 24, 2016

The Khorasan, considered to be Islamic State (IS, formerly ISIS/ISIL) terrorist group's arm in Afghanistan and Pakistan, reportedly claimed responsibility for the attack.

Police stationed outside a Police Training Center, #Quetta, #Pakistan; 5 to 6 jihadists have taken hostages in the center.

via " channel1iba pic.twitter.com/DaqZZjxbw8 — Raven*H⚓️U*Wolf (@RavenHUWolf) October 24, 2016

Meanwhile Pakistan’s Major General Sher Afghan blamed the Lashkar-e-Jhangvi al-Alami terrorist group for orchestrating the attack, claiming that Monday night’s assailants received their directions from Afghanistan.

The attack has been condemned by the Prime Minister Nawaz Sharif, who went on to order the security forces to further guard and protect the police cadets.