Copenhagen  - A Danish student has been arrested in Iran during protests earlier this week, the Danish Union of Journalists said Friday.

The Danish journalist union said the Brussels-based International Federation of Journalists (IFJ) had helped trace Niels Krogsgard.

Krogsgard, a student at the University of Southern Denmark, went missing Wednesday. A fellow Danish student alerted the Danish embassy in Tehran when Krogsgard did not turn up to a meeting.

The two students were in Iran to write an essay on Iranian politics.

Danish authorities have not been able to contact Krogsgard, and were trying to establish where he was held.

Several reporters have been reported arrested in connection with protests held Wednesday near the former American embassy in Tehran.

In recent months Iranian authorities have apparently prohibited foreign media from directly covering protests or making contact with opposition figures.(dpa)