The Pakistan Cricket Board provisionally suspended Sharjeel Khan and Khalid Latif under its anti-corruption code on Friday and dumped the pair out of the Pakistan Super League, just one day after the Twenty20 event started.
"Sharjeel and Latif have been suspended and the rigorous and wide-ranging investigation by the PCB supported by the International Cricket Council will continue as part of collective efforts to protect the integrity of the sport," the board said in a statement.
No further details were released but the pair were thought to be linked to spot-fixing, an illegal betting practice rife in Pakistan cricket in recent years.
The PSL said that the investigation centred on "an international syndicate which is believed to be attempting to corrupt the PSL".
Sharjeel played in the opening match of the 2017 PSL on Thursday for Islamabad United, scoring just one run off four balls against Peshawar Zalmi. Latif was not part of the starting team.
Islamabad won the game by seven wickets.
Sharjeel, 27, was part of the Pakistan team which recently toured Australia and featured in a Test and all five one-day internationals. He has totalled 25 one-day internationals and 15 Twenty20s.
Latif, 31, was part of Pakistan's World Twenty20 squad in India last year and has played five one-day internationals and 13 Twenty20s.
Najam Sethi, chairman of the Pakistan Super League said: "It would not be appropriate to comment on the specifics of the case, however this investigation is a clear demonstration of our determination to drive corruption out of our sport.
"We will not tolerate any form of corrupt activity and as this investigation proceeds we will not hesitate to take further decisive action as appropriate."
PCB chairman Shaharyar Khan said players should know the pitfalls of corruption.
"Under no circumstances will the PCB condone actions of a few individuals to bring disrepute to the game of cricket or taint the image of Pakistan," he said.
Khan later told media gathered at Karachi airport that evidence of wrongdoing exists.
"We have evidence against the players and we are into further investigation," Khan said.
"Sharjeel was on my flight back from Dubai but we did not meet."
Defending champions Islamabad, who are in action again on Saturday, said they would be looking to bring in replacements for the banned Sharjeel and Latif.
"We are understandably disappointed at this development but emphasise our commitment to a zero-tolerance policy towards any violations of the rules or stated guidelines," the team said in a statement.
"We will be looking to find replacements for the squad as soon as possible. As per the PCB's policy and guidelines, we will have no further comment on this issue."
Pakistan cricket has been rocked by fixing scandals over the past several years.
Former captain Salim Malik and Ataur Rehman were banned for life after an investigation in 2000.
Malik was punished for offering Australian trio Shane Warne, Tim May and Mark Waugh a bribe to underperform during their visit to Pakistan in 1995.
In 2010 then Test captain Salman Butt, Mohammad Amir and Mohammad Asif were jailed and banned for five years for spot-fixing while leg-spinner Danish Kaneria was banned for life in a spot-fixing case in 2012.
The suspension is likely to end Sharjeel's contract with English county side Leicestershire to play the Twenty20 Blast tournament later this year.
A spokesman told AFP that the club would be making no comment on the investigation or the status of Sharjeel's contract.