The assailant was subdued with a taser before he could injure the police.
A 29-year-old man armed with a knife was arrested on Monday after he attacked two police officers in London, not far from Downing street
The incident did not cause any injuries and is not considered to be terrorism in nature, according to the police.
The suspect was taken into custody for attempted murder and possession of a weapon, Scotland Yard said in a statement.
The facts occurred shortly before 9 a.m. at Horse Guards Parade, an esplanade which adjoins the back of Downing Street, the residence of Prime Minister Boris Johnson.
The police used their stun gun and the suspect was subdued, said Scotland Yard, which appealed for witnesses.
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