Home Minister Rajnath Singh today called up Kerala Chief Minister Pinarayi Vijayan over recent political incidents of violence in the state including attack on a BJP office in Thiruvananthapuram. In a tweet, he said the Chief Minister has assured him of effective action.<br/><br/>A crude bomb was hurled at a BJP office in Thiruvananthapuram on Tuesday night with the party alleging that ruling CPI(M) workers were behind the attack. However, CPI(M) has rejected the allegation.