Of those, 427 are more risky, the sources added.

Additional Divisional Commissioner (General) and Returning Officer Mohammad Golam Kuddus said centres with possibilities of coming under criminal attacks and communications problems have been marked as risky ones.

He said around 12,000 polling agents and presiding officers will be deployed to hold the elections and they will be given training on May 3, 4 and 5.

In addition to six companies of army, 10,000 police, 20,000 Ansar, BDR, RRF and Rab personnel will be in place to ensure security.

Replying to a question, Kuddus said the Election Commission will hold separate meetings with the mayoral and commissioner candidates. The date of the meeting is yet to be announced.