Key Pakistani opposition leader and former chief minister of central-eastern Punjab province, Chaudhry Pervaiz Elahi, has been arrested in a graft case, officials and his family confirmed.

Elahi, who has recently been appointed as president of former Prime Minister Imran Khan's Pakistan Tehreek-e-Insaf (PTI) party, was arrested on Thursday by anti-corruption authorities in the provincial capital Lahore.

"Pervez Elahi is wanted in several corruption cases," Amir Mir, caretaker information minister in the eastern province of Punjab, told Reuters news agency.

He added that Punjab's anti-corruption department had been looking for Elahi for several days. Elahi previously denied accusations of corruption.

Footage aired on local broadcaster Samaa News showed police breaking the windowpane of Elahi's vehicle as he apparently resisted surrendering.

Another video shows police pushing him to the security van outside his Lahore home.

Pakistan is facing political turmoil since Khan's own arrest on May 9 for suspected graft sparked widespread protests that saw mobs ransacking state installations, including military assets.

Khan was freed on bail on May 12 for an initial two weeks, obtained a three-day bail extension from a high court and later a further extension from the trial court until June 19.

Dozens of top and mid-tier leaders in the PTI have been arrested alongside hundreds of Khan supporters since the violent protests of May 9.

The PTI claims that over 7,000 of its workers and supporters have been arrested since May. The government, for its part, confirms some 4,000 arrests.

Khan, who denies wrongdoing, says the arrests are part of a campaign to dismantle his party and that the state is using pressure tactics to force out his aides. The government denies this and says his aides were leaving of their own volition.