The number of suicides in England and Wales fell by about 40 percent after the July 2005 bombings on London, scientists revealed Tuesday, echoing a trend also seen after the September 11 attacks.
Two researchers found a "small but significant reduction" in the daily suicide count five days after the attacks on July 7 that killed 52 people, they reported in the British Journal of Psychology.
Suicide rates also dropped on July 21, 2005 when bombers again targeted the capital but failed to detonate their explosives.
Psychologists believe traumatic national events such as these help potentially suicidal people to feel less alone and more a part of society.
An analysis of official daily suicide counts between January 1, 2001 and December 31, 2005, revealed suicide rates fell by about 40 percent on July 12 and July 21. No such drop was seen at this time in the previous four years.
After the attacks in the United States on September 11, 2001, suicide rates also dropped in Britain by about the same proportion.
The researchers, Dr Mario Cortina-Borja, from University College London, and Emad Salib, from the University of Liverpool, expressed surprise that the London bombings did not have a greater effect on Britain than the US attacks.
They suggested that previous experience of attacks by the Irish Republican Army (IRA) may have reduced the psychological impact of terror campaigns.
"It is possible that previous experience of IRA terrorism in the UK may have limited the effect of the 7 July 2005 attacks on suicide in England and Wales," they wrote in the January edition of the journal.
"The shock value of suicide terrorism and its psychological potency appear to diminish over time as the tactic becomes overused."
They added: "The terrorist attacks in London had been expected and, prior to 7 July 2005, attempts had been made by the British government to prepare the UK population for a possible major incident.
"This may have led to a relatively weaker emotional impact compared with the totally unexpected 11 September 2001 attacks in New York."
The latest figures made public by the Office for National Statistics show there were 5,906 adult suicides in 2004, an average of 16 a day.