Peshawar police on Tuesday claimed to have arrested a man who, along with an accomplice, allegedly shot dead a professor belonging to the Ahmadi community in the city a day earlier.

Dr Naeemuddin Khattak, a zoology professor at Superior Science College on the outskirts of Peshawar, was going home when two men riding a motorcycle opened fire on his car in the Wazir Bagh area. He died on the spot.

The arrested suspect, identified as Mubasir, is a "close relative" of the deceased, a Peshawar police statement said.

On Monday, police had registered a case against Mubasir and a fellow academic of Khattak, Saad Farooq, for allegedly being involved in the murder.

The two suspects were directly named in the first information report (FIR) by Khattak's family. They reportedly had a heated argument with the slain professor over a religious issue a day before his murder.

Moharrar Ashoor Khan at Bhana Mari police station, in whose jurisdiction the killing took place, told Dawn.com that a police team raided a house in Lala Rukh Colony in Syed Hassan Pir area and arrested Mubasir.

He said the other suspect, Farooq, a lecturer at the University of Agriculture, Peshawar, was at large. Khan added that police were investigating the case and hoped that the second suspect would be arrested soon.

According to the police official, initial investigation suggested that the professor was killed over his religious beliefs.

The deceased's body was handed over to his family after postmortem and he was subsequently laid to rest.

Suspect Mubasir was still being questioned, police official Ayaz Khan told the Associated Press. He will be presented before a judicial magistrate on Wednesday for obtaining his physical remand, the moharrar said.

This was the third murder of a member of the Ahmadi community in Peshawar since July 29, when Tahir Naseem, an American national, was shot dead by a teenager in a court. On August 12, Meraj Ahmed, an Ahmadi trader, was shot dead by attackers in the Gulbahar area.

On September 10, a mob besieged the residence of an Ahmadi in the Phandu area of the city and the family was rescued by police. However, one of the family members was arrested and charged with blasphemy.