Kolkata, May 9 (IANS) Four coronavirus positive cases were reported on Saturday in West Bengal's North Dinajpur district, which was so far a "green zone".

In another north Bengal district of Malda, at least four persons tested corona positive on Saturday.

"Four positive cases have been reported in three areas of North Dinajpur district -- two cases at Raigunj and one each in Hemtabad and Shyampur," said North Dinajpur District Magistrate Arvind Meena said.

North Dinajpur was one of the eight green zone districts of West Bengal as no corona cases were reported there in the past weeks.

Meena said that these four patients had travelled to the district from Kolkata. "We are taking necessary steps to find out every aspect of the development," he added.

--IANS sbn/tsb