A security expert wants more scrutiny of foreign students coming here to study.

It's after a man who studied at university here was gunned down and killed by police in Saudi Arabia.

They say Taie bin Salem bin Yaslam al-Saya'ari planned a deadly attack last year at one of Islam's holiest sites.

Four people were killed at the Medina mosque.

Security expert Paul Buchanan thinks the man studied engineering at Auckland University some time ago.

He says there's no security vetting of students who come to schools or universities here from Saudi Arabia, or other hotbeds of extremism such like Pakistan.

In fact, Paul Buchanan says there are favourable visa schemes for students from both these countries.