By Victoria Ward 27/3/08

Kate and Gerry McCann last night urged police to probe where a suspected child murderer was when Madeleine went missing.

The Spaniard, 52, has been held on suspicion of killing Mari Luz Cortes, five – snatched 90 minutes away from where their daughter went missing.

The McCanns want Portuguese police to rule out any link between the two cases. The suspect, a convicted paedophile, has allegedly confessed to Mari’s murder.

She vanished 100 yards from her home in Huelva, Spain, in January after going to buy crisps. Her body was found in a river.

Madeleine, four, went missing in Praia da Luz, Portugal, last May.

The McCanns’ spokesman Clarence Mitchell said: “It’s important that police make sure there’s no connection now there’s been an arrest.”

Kate and Gerry will take part in an ITV documentary in the run-up to the first anniversary of the disappearance.