MONTREAL -- Quebec Premier Philippe Couillard says he acted diligently this week in dealing with a former cabinet minister who is facing a provincial police investigation.

Couillard tried Friday to clarify the circumstances surrounding the departure of Pierre Paradis as opposition parties raised questions about the premier's transparency on the matter.

Late on Thursday, Couillard's office said Paradis, 66, had been replaced as agriculture minister by Laurent Lessard and kicked out of caucus.

Paradis has represented the riding of Brome-Missisquoi since 1980.

Couillard told reporters Friday he was first informed of a complaint against Paradis one week ago while attending the Davos economic summit.

On Tuesday, his office received a letter from the complainant and Paradis was removed from cabinet temporarily on Wednesday without any reason given.

"We received a letter from the person saying she or he has been the victim of these incidents, which led to the immediate removal of Mr. Paradis (temporarily) from cabinet," Couillard said.

"Yesterday (Thursday) evening, we had confirmation that (Quebec provincial police) had opened a formal inquiry on this. Given that information, I decided to act immediately and asked Mr. Paradis to leave cabinet and caucus."

Paradis has not been charged with any crime and Couillard declined to elaborate on the nature of the criminal complaint.

Opposition parties in Quebec City pounced on the matter, questioning the government's transparency on the matter.

The Parti Quebecois' Agnes Maltais said she wants a detailed account of the events between last week, when police first contacted Couillard's office regarding Paradis, and Thursday, when Couillard was told he was the subject of an investigation.

On Wednesday, a spokeswoman for Paradis said he was stepping away from his cabinet duties temporarily after falling off a horse and suffering a concussion.

Laurence Lemieux described the concussion as mild and said he suffered no fracture.

Couillard confirmed Paradis' health problems.

"According to the information I have, Mr. Paradis was indeed the victim of an accident and a concussion and is under medical care," he said.

"But this is not the reason he was asked to leave cabinet -- first on a temporary basis on Wednesday and permanently (on Thursday)."