Romanian border police have questioned 30 migrants who are suspected of illegally entering Romania from Serbia.

Police used heat-detecting equipment to spot the migrants, 29 Afghans and a Pakistani man, who were hiding in fields early Monday on the border between Serbia and southwestern Romania.

Border police and local police rounded up the men and drove them to the local border police headquarters for questioning.

A statement said none of migrants was carrying documents. They told Romanian authorities they wanted to reach western Europe.

Romanian police have contacted Serbian police to help with the probe.