A second man has been arrested in connection with an alleged terror incident near Buckingham Palace.
Three officers suffered minor injuries on Friday night when a suspect deliberately drove a car at police outside the Palace and then "reached for a four foot sword".
On Sunday morning, a 30-year-old man was arrested in West London in connection with the incident.
A Metropolitan Police spokesman said: "The man was arrested on suspicion of being involved in the commission, preparation or instigation of terrorism at 10.15am and he has been taken into custody.
"Police are searching an address in West London as part of this inquiry."
A 26-year-old man from the Luton area was arrested on Friday night after the incident.
He was initially arrested at the scene on suspicion of grievous bodily harm and an assault on police and has since been further detained under the Terrorism Act.