LONDON, March 22 (Reuters) - The number or people who died in an attack close to Britain's parliament on Wednesday has risen to five after the death of a third member of the public, police said.

Previously, the death toll had stood as four, including the attacker and a police officer.

Britain's top counter-terrorism police officer Mark Rowley told reporters that police believed the attacker was inspired by Islamist-related terrorism. Rowley said police believed they knew the identity of the attacker but he declined to provide details.

(Reporting by William Schomberg and Michael Holden; Editing by Jonathan Oatis) ((william.schomberg@thomsonreuters.com; +44 207 542 7778; Reuters Messaging: william.schomberg.reuters.com@reuters.net))

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