BY A STAFF REPORTER: BJP's Kerala unit has received a threat letter ahead of Prime Minister Narendra Modi's visit. After that, the entire state has been put on high alert. The man who sent a letter to Kerala BJP president K Surendran threatened to carry out a suicide bomb blast during Prime Minister Narendra Modi's program in Kochi on April 24. He handed over the threat letter to the police, which also had a name and address written on it. The police immediately reached the address, which was mentioned in the letter.