Premier League champions Liverpool said they were "deeply saddened" by the loss of treble-winning manager, Gerard Houllier after his death was announced on Monday.

Paris Saint-Germain and Lens confirmed the death of Houllier, who managed Liverpool from 1998 to 2004. He was also France national coach from 1992 to 1993.

The Frenchman led Liverpool to a treble of League Cup, FA Cup and UEFA Cup in 2000/01 and returned the club to the Champions League.

"The thoughts of everyone at Liverpool Football Club are with Gerard’s family and many friends," the club said in a statement. "Rest in peace, Gerard Houllier 1947-2020." 

Houllier, 73, who recovered from life-saving heart surgery during the 2001/02 campaign to return to the dugout, later guided Liverpool to a second League Cup triumph.

He left the following year after overseeing 307 matches and successfully re-establishing the club as a modern force.

In October 2001, Houllier fell ill at half-time during Liverpool's match against Leeds and was diagnosed with an aortic dissection, which required emergency surgery and led to a five-month spell out of the dugout.

He suffered further health problems during a later management spell with Aston Villa. He was admitted to hospital in April 2011 after falling ill, and did not return work before stepping down by mutual consent in June.

Houllier died after undergoing heart surgery. 

Former Liverpool and England forward Michael Owen described him as a "genuinely caring man", while ex-striker Ian Rush called him a "true gentleman".

Former Liverpool defender Jamie Carragher tweeted: "Absolutely devastated by the news about Gerard Houllier, I was in touch with him only last month to arrange him coming to Liverpool. Loved that man to bits, he changed me as a person & as a player & got @LFC back winning trophies. RIP Boss. "