The Hague city councillor Arnoud van Doorn was arrested on Sunday on suspicion of planning to kill prime minister Mark Rutte, the AD reported on Tuesday afternoon.

Van Doorn, a former councillor for the far right PVV who went on to convert to Islam and form his own splinter party, was ‘seen to act suspiciously’ as he was walking around a neighbourhood where Rutte was at that time, a police spokesman said.

Van Doorn, who in 2014 was fined for keeping an alarm gun under his bed and selling drugs to minors, was held for a night and released after questioning the following morning.

His lawyer Anis Boumanial said the action was prompted by fear. ‘There was no reasonable presumption of guilt and my client should not have been arrested. It doesn’t matter if it’s about Rutte or someone else,’ he told the AD.

A spokesman for the public prosecution office said Van Doorn ‘behaved suspiciously’ and was attempting to gather information to aid the preparation for an serious crime. ‘That soon leads to suspicion of an intent to commit murder,’ he said without elaborating further.

Rutte was given extra personal protection on Monday amid concern that gangsters may be plotting to kidnap him.

The Telegraaf reported that intelligence agencies acted after ‘spotters’ – people hired by criminal gangs to prepare the ground for an attack or kidnap – were observed in Rutte’s vicinity. The prime minister was reportedly initially reluctant to accept the extra protection.