Revival MP Petar Petrov told reporters in parliament's corridors that the party has asked interior minister Ivan Demerdzhiev and acting interior ministry chief secretary Lyubomir Nikolov to answer MPs' questions over the killing of Botev Plovdiv football club president Iliyan Filipov.

Revival wants the hearing held tomorrow, at a meeting of parliament's committee on internal security and public order.

"We think it's important to find out how the interior ministry is organized when it comes to solving this crime quickly, and to preventing crimes like it," Petrov said.

Petrov called the case a worrying sign, made worse by the political climate and the start of the election campaign. He said Bulgaria could slide back to the past, even though prime minister Rumen Radev has said the fight against oligarchy is over.

"This has even changed parliament's agenda," Petrov added.

Hours earlier, Plovdiv district prosecutors said they were overseeing a pre-trial investigation into the deliberate killing of a Plovdiv businessman identified only by the initials I.F. Botev Plovdiv's management later confirmed the victim was Iliyan Filipov.

Updated (01.10, 10:16): According to BTA, the request for a hearing on the Plovdiv murder was filed again by Pro Bulgaria, not by Revival as first reported. Lawmakers voted unanimously, 203 in favour, to hear interior minister Ivan Demerdzhiev, which is the first item on today's plenary agenda.

Updated (01.10, 10:34): Police have arrested the man suspected of carrying out the killing of Iliyan Filipov, interior minister Ivan Demerdzhiev told parliament. Officers made the arrest in Sofia late yesterday afternoon and gathered evidence at the scene. Demerdzhiev said the interior ministry is checking whether anyone else was involved, but a check carried out yesterday within the ministry's own ranks found no such links.

Follow-up: Weapon used to kill Iliyan Filipov in Plovdiv still not found