"There is no evidence that Masood was radicalised in prison in 2003, as has been suggested; this is pure speculation at this time. Whilst I have found no evidence of an association with IS [Islamic State] or AQ [al-Qaeda], there is clearly an interest in Jihad," Senior National Coordinator for UK Counter Terrorism Policing Neil Basu said, as quoted in the statement.
Basu added that Masood’s minimalist attack method resembled those of Daesh terrorists "in terms of methodology and attacking police and civilians," but it is still not known whether or not he discussed the terrorist act with anyone prior to committing it.
The attacker was born in Kent and lived in West Midlands, according to Metropolitan Police. He had several previous convictions for assaults and possession of offensive weapons. The last conviction was in 2003.