Updated

A Frenchman suspected in the shooting deaths of three people at the Brussels Jewish Museum is formally opposing extradition to Belgium.

Masked, armed police special forces guarded Mehdi Nemmouche as he appeared in a Versailles court Thursday. The 29-year-old is believed to have had contact with Islamic extremists in Syria. He was arrested last week in the probe into the May 24 killings.

In court, Nemmouche said he didn't consent to the extradition based on a European arrest warrant. The refusal was likely to prolong the process as authorities explore options.

His lawyer says there's no proof that his client was the shooter and argues that he should be tried in France because he is a French citizen and French authorities are equally competent.

Nemmouche also has Algerian citizenship.