KARACHI: One of the injured suspects from Saturday's Patel Para blast in Karachi told investigators that the home-made explosive device was being prepared to target a Yaum-e-Ali procession, DawnNews reported.

The wounded suspect who was in police custody also confessed that the one of the persons who had died in the accidental explosion was an expert bomb-maker and an important member of a proscribed religious organisation.

He added that the bomb-maker had been picked up by security personnel six months back.

The suspect further said that the bomb which went off accidentally on Saturday was being prepared to target a Yaum-e-Ali procession.

At least four people were killed and several others, including a senior government official, were injured when two separate blasts shook Karachi Saturday evening.

The first explosion took place shortly before sundown near Esa Nagri graveyard in Gulshan-i-Iqbal, close to the busy Hasan Square area.

Police said the bomb targeted the government vehicle of KMC Metropolitan Commissioner Matanat Ali Khan after he left his office at Civic Centre for home almost an hour before sunset. Initially the police described the incident as a grenade attack, but the impact of the explosion forced them to change their opinion.

“Apparently the bomb was planted in a motorcycle, eight people have been injured, condition of some of them is critical,” said Nasir Lodhi, a senior police official in Karachi.

The explosion was so powerful that it destroyed the double-cabin vehicle of Mr Khan and three stationary motorcycles, damaged two rickshaws and smashed windowpanes of several flats.

Other than Mr Khan, the blast left three other people injured. They were taken to Abbasi Shaheed Hospital and Aga Khan Hospital. They included his guard, constable Sohail Anjum Siddiqi, who suffered head injuries and died in hospital, an official said.

Lodhi said the senior government official was the target “but motives and causes of the attack are yet to be investigated.”

Governor Sindh Dr Ishratul Ibad later sought a report from the Inspector General of Sindh Police, who formed a team headed by the DIG Police East to investigate the incident.

While police were busy collecting evidence from the scene, another explosion inside a flat in Patel Para left three people dead and one injured. Police said the blast occurred on the third floor of a three-storey building, which was rented out only four days ago.

“The three-storey structure has been built on a 60-yard plot in a narrow street,” said SP Raja Umer Khattab of the CID’s counter-terrorism unit. “It seems that the blast occurred when explosive material also containing ball bearings was mishandled by the people in the flat.

Evidence gathered from the site suggested the three suspected terrorists were apparently killed when a bomb they were making accidentally exploded.

Police took into custody the injured man for further interrogation.

Karachi, a city of 18 million people, contributes 42 per cent of Pakistan's GDP but is rife with murder and kidnappings and has been plagued for years by ethnic, sectarian and political violence.