A member of the Tamil National Alliance, he was shot dead on Christmas Day 2005 as he attended midnight mass at St. Mary's Cathedral, Batticaloa.

[4][5][8] Pararajasingham was a staunch supporter of Illankai Tamil Arasu Kachchi (ITAK), commonly known as Federal Party, and at the 1970 parliamentary election he and his wife supported ITAK candidate C. Rajadurai rather than their relative P. R. Selvanayagam who was contesting as an independent candidate.

[9] After retirement Pararajasingham tried to operate several businesses including mineral water manufacturing and wholesale paper sales.

[4][5][9] Pararajasingham also worked as a freelance journalist, initially writing for the Suthanthiran owned by S. J. V. Chelvanayakam, leader of ITAK.

[4][5][8] Whilst working for the government his articles were credited to his wife Sugunam Joseph but after retirement he wrote under his own name, P.

[4] Pararajasingham was an active social worker - he was secretary of the Parents' Association and the Batticaloa Red Cross Society.

[9] Pararajasingham would telephone, fax and write to ministers, civil servants, the military and the police to seek assistance for the civilians.

[27][28] Pararajasingham and others founded NESOHR (North East Secretariat on Human Rights) on 9 July 2004.

[5][18][31] A group of men in military clothing arrived at the nearby St. Anthony's Church and changed into civilian dress.

[18] As Pararajasingham returned to his pew the men started firing, causing the congregation, including the Bishop, to dive to the floor.

[18] Some eyewitnesses reported that the gunmen left in a rickshaw and headed towards the Patpodi camp, an old tooth powder factory used by the government-backed Karuna Group/TMVP paramilitary group.

[18] The police bodyguards claimed that they didn't want to fire inside the cathedral in case they hit the worshippers.

[18] Prior to the shooting, when worshippers were entering the cathedral they noticed that the surrounding area was teeming with security personnel.

[18] It is widely believed that the assassination was sanctioned by the Sri Lankan government/military and carried out by the government-backed Karuna Group/TMVP paramilitary group.

[5][38] A few weeks after the assassination Sugunam was given a visitor visa by Canada where her son and daughter were living as Canadian citizens.

[40] In July 2009 an Immigration and Refugee Board hearing began and in February 2011 the adjudicator ruled that Sugunam was a "terrorist" and ordered her deportation.

[32] In July 2006 two suspects were arrested but, after a failed identity parade in August 2006, both were released due to "lack of evidence".

[42] Two TMVP paramilitaries, Pradeep Master (Edwin Silva Krishnanandaraja) and Gajan Maamaa (Rangasami Kanaganayagam), were arrested by the Criminal Investigation Department (CID) on 8 October 2015 in connection with Pararajasingham's assassination.