Washington, April 27 -- The shooting at the White House Correspondents' Dinner has sparked a fresh debate over security, as questions mount over how a heavily armed suspect was able to get so close to an event attended by President Donald Trump and other senior officials.

Investigators say the suspect, 31-year-old Cole Tomas Allen, mocked what he described as an "insane" lack of security in a manifesto sent to family members minutes before the attack. In it, he claimed he had entered the venue carrying multiple weapons without raising suspicion, writing that "not a single person there considers the possibility that I could be a threat".

Allen, a Caltech graduate, expressed hostility towards Trump and his administration in the document. Au...