Thiruvananthapuram, Aug 14 (IANS): Three trains travelling through Kannur and Kasargod districts in Kerala were pelted with stones, said officials on Monday.

The incident happened on Sunday night, and the Southern Railway officials have taken a serious note of this.

What has baffled the Railway Police is the timing of the stoning as it happened between 7.11 pm and 7.16 pm when two trains that left Kannur railway station and were bound to Kasargod. The trains were stoned near Valapattanam . The third train was stoned at Nileshweram, when it had left Kasargod for Kannur.

Even though the police have taken into custody four migrant workers from Valapattanam who were found in an inebriated state, they have claimed that they have done no wrong.

Incidentally, it was in Kannur district that a Vande Bharat train was also stoned a few weeks ago.

The Railways has taken the incident seriously in view of the April 2nd incident when a train bound for Kannur from Kozhikode was set on fire by a 27-year-old Delhi resident, Shahrukh Saifi.

The case is being investigated by the NIA and Saifi is presently under judicial custody.

The Kerala Police also have been roped in and on Monday more probe will take place.