Bangkok Police on Saturday arrested Abdul Rehman, alias Bhola, the alleged frontman in the 2012 arson attack at Karachi's Baldia garment factory in which 250 workers were burnt alive, Thai police said Saturday.

Abdul Rehman, 46, was detained at a hotel in the red light district Nana area of the capital on Friday evening, said Thailand's Interpol chief.

Pakistani authorities had named Abdul Rehman, who was then a sector in-charge of the Muttahida Qaumi Movement (MQM), as the suspect who allegedly lit the fire.

Rehman was arrested by the Federal Investigation Agency (FIA) with the help of Interpol, said Additional IG Mushtaq Mahar.

“As per existing law, the FIA is authorised to arrest an absconder from another country with the help of Interpol,” said the AIG.

He further added Rehman’s custody will be handed over to the Sindh Police once he is brought back to the country for further investigation and legal proceedings.

“Thai Interpol tracked this suspect following an arrest warrant sought by the Pakistani authorities,” Major General Apichart Suriboonya told AFP.

“He will be repatriated as soon as Pakistan is ready,” he added.

Read: Baldia factory fire was a ‘planned terrorist activity’, says JIT report

When asked Saturday whether he could confirm if Abdul Rehman was an MQM sector in-charge or not, MQM leader Rauf Siddiqui said: "This is not in my knowledge. Party's convener and deputy convener know these things as set ups keep changing."

The fire at the Ali Enterprises factory in September 2012 was one of Pakistan's worst industrial disasters.

A judicial probe into the blaze was damning, pointing to a lack of emergency exits, poor safety training for workers, the packing in of machinery and the failure of government inspectors to spot any of these faults.

Initially the fire was believed to be an accident but a Joint Investigation Team ‘reinvestigating’ the case this year termed the incident a “planned sabotage and terrorist activity”.

'Those involved in crimes against people will not be spared'

Chief Minister Sindh Syed Murad Ali Shah, while commenting on the arrest of Abdul Rehman in Bangkok, said those involved in crimes against the people will not be spared.

"Baldia factory fire was one of the worst incidents to ever take place in the city in which innocent labourers were burnt alive," said the chief minister.

He added that criminals who were involved in the incident would be found and brought to justice.

The 'reinvestigation'

Police had filed the supplementary charge sheet in August under the anti-terrorism law following a lengthy reinvestigation of the case.

According to the supplementary report, former chief of the MQM Karachi Tanzeemi Committee Hammad Siddiqui, his alleged front man and then Baldia Town sector in-charge Abdul Rehman, alias Bhola, and three to four unknown men were named as absconders in the case while around a dozen others were left out for lack of evidence and the owners of the ill-fated industrial unit were listed among the prosecution witnesses.

Initially, the police had charge-sheeted the owners and some employees of the factory in the tragic incident. However, the reinvestigation of the case was ordered in March last year through a joint investigation team after a JIT report submitted in the Sindh High Court in February 2015 revealed that the factory was set on fire after its owners failed to pay protection money.

The JIT had named Hammad, Abdul Rehman, Zubair, Ali Hasan, Umar Hasan, Abdul Sattar, Iqbal Adeeb Khanum and four unidentified persons as proposed accused in the report. However, police contended that incriminating evidence was available only against the two proposed accused.

Much of the factory's garment output went to the German company KIK, who have paid out nearly two million dollars in compensation to the victims' families.