Pakistan fast bowler Mohammad Irfan and batsman Shahzaib Hasan have been summoned by the PCB in relation to their investigation into alleged corruption in the PSL. Both men had been called in for questioning by the anti-corruption unit in Dubai last month but were given a clean chit to continue playing the tournament. Now, a PCB spokesman said, they face the possibility of being charged.

Two cricketers - Sharjeel Khan and Khalid Latif - have already been charged by the PCB for various code-of-conduct breaches, including attempting to corrupt a cricket match. A three-member tribunal has been set up to hear their cases next week in Lahore.

Irfan and Shahzaib had previously come forward to report approaches made on them at the PSL. They have now been recalled so that the anti-corruption unit could vet their stories.

"PCB has initiated the investigation from the lead left in Dubai," A spokesman told reporters at Gaddafi Stadium in Lahore. "It has started with both [Shahzaib and Irfan] being issued a demand note and by that both are bound to share all the information with PCB anti-corruption unit.

"Irfan has been summoned to appear on Monday while Shahzaib has been asked to appear on Tuesday. PCB anti-corruption unit will assess their evidence and information and will determine whether to charge them or not."

Amid the ongoing investigation, Irfan has not been selected in a pool of 31 players to undergo a training camp ahead of the West Indies tour. Shahzaib, however, has not been in contention for a place in the national team since 2010, when he played the last of his three ODIs and 10 T20Is. Sharjeel and Latif are currently provisionally suspended.

Umar Farooq is ESPNcricinfo's Pakistan correspondent