David M. Benett/Dave Benett/Getty Images for BGC Partners(LONDON) — The United Kingdom has seen five terrorist attacks this year, but London Mayor Sadiq Khan said on Sunday that more attacks have been foiled.

Since March, seven terrorist plots have been thwarted, he said.

“The phrase used by police experts, counterterror experts in relation to terrorism is what we’re seeing is not a spike but a shift,” Khan told a Guardian live event at an annual conference of his Labour Party, in Brighton, England. “If you look at the time between March of this year and now, yes, there have been four terrorist attacks [in London], but there have been seven that have been thwarted.”

This year London saw four attacks: at Westminster, at London Bridge, against Muslim worshippers near Finsbury Park Mosque and at Parson’s Green in the London subway. The U.K. also saw an attack this year in Manchester, England, after an Ariana Grande concert.

The number made public by Khan is higher than the number previously released. Earlier this month, the head of London’s Metropolitan Police, Neil Basu, said six plots have been thwarted since March.

Khan’s comments came amid the investigation into the Parson’s Green attack. On Monday the city’s police force said it arrested a seventh person, a 20-year-old man, in connection with the attack, which wounded dozens of people. Three of the seven arrested have been released, one has been charged, and three remain in custody. Police are also carrying out searches at various addresses in England.

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