Thiruvananthapuram: Former chief minister and CPM stalwart V S Achuthanandan turned 99 on Thursday.

Fondly called 'Comrade VS' by his followers and fans, Achuthanandan has been keeping away from public and media glare for quite some time due to age-related difficulties.

According to party sources, the veteran celebrated the day along with members of his family here and visitors were not allowed to extend wishes considering his health condition.

Marking the day, Achuthanandan's son V A Arun Kumar said in his Facebook page that "Today is my father's 99th birthday". He also said he was blessed to be born as the son of such a great personality who is entering his 100th year.

Cutting across party and political lines, people from various walks of life greeted the Marxist leader, who is the founder-leader of CPM after the split in the undivided CPI in 1964.

Governor Arif Mohammed Khan said he joined the people of Kerala in wishing Achuthanandan good health and happiness.

"Conveyed heartiest birthday greetings to former Chief Minister Shri VS Achuthanandan through his son," he tweeted.

Chief Minister Pinarayi Vijayan said in his Facebook post: "Hearty wishes to dear Comrade VS, who is celebrating his 99th birthday."

Extending his greetings, senior Congress leader Jairam Ramesh described Achuthanandan as the "titan of Kerala politics".

"VS Achuthanandan, a titan of Kerala politics, officially turns 99 today. Many believe he's already crossed 100. I recall my interactions with him when he was CM fondly. He was authoritative, not authoritarian," he tweeted.

He also criticised the party mouthpiece 'Deshabhimani' for ignoring the veteran on the day.

"Strange today's front page of Deshabhimani ignores this milestone," Ramesh added.

Born on October 20, 1923, in a working-class family in the Alappuzha district, Velikkakath Sankaran Achuthanandan became part of the trade union after ending his formal education at the primary level. Joining the Communist movement, his life is linked with its history in the state including the Punnapra-Vayalar uprising, underground activities of the party after it was banned in 1949 following Calcutta thesis and the formation of the CPM following the split in the CPI in 1964.

Achuthanandan, who became a CPM politburo member in 1996, headed the CPM-led LDF government in 2006-11, defeating efforts by his rivals in the party to deny him a chance. He is staying at his son's residence here after stepping down as Chairman of the Administrative Reforms Commission last year.

(With PTI inputs)