Kochi: The letter threatening to kill Prime Minister Narendra Modi in Kerala was dispatched to BJP's Kerala chief K Surendran in the name of Kaloor native NK Johnny.

"The police visited our house on Tuesday. They realised that the handwriting in the letter was not mine," Johnny said while responding to the media on Saturday.

Last week, BJP leader Surendran had received a letter claiming a conspiracy to assassinate PM Modi. The letter hinted at a suicide attack against the PM during his Kerala trip.

A report forwarded by the Intelligence Additional Director General of Police T K Vinod Kumar ahead of the PM's trip early next week has warned of a security threat in Kerala. The report, which leaked in the public domain, mentions the letter in Johnny's name.

"The police first visited our house four days ago. A man called at my residence and asked if my name was Johnson Joseph. When my family members replied that it was Johnny, he enquired about my whereabouts. The correct address was provided. After five minutes, he rang up again and asked for Joseph Johnny. He also asked if I had written a letter to anyone on a postcard," Johnny said.

"When the police arrived, they showed me a copy of the letter on their smart phone. I picked a diary and showed them my handwriting. The police clicked pictures of my handwriting. Back in June 1, 2014, I had received a complaint letter while functioning as the leader of a family unit at the church. The handwriting in the complaint was identical to the one in that letter. The police also realised the similarity."

Johnny also alleged that the person who worte the 2014 letter was a constant trouble-maker. In April, he had warned Johnny of repercussions when they had an argument.

"The police had read out the letter to me. It stated that Modi will meet Rajiv Gandhi's fate. The name Joseph John was included in the letter along with my mobile number. It was an old BSNL number which I do not use anymore."

Former Prime Minister Rajiv Gandhi was killed in a suicide blast in 1991.

"I am a retired officer. My wife is a teacher. I have undergone surgery, and suffer from high-blood pressure and cholesterol. I leave the house only to visit the shop. I was shocked when I heard this," said Johnny.

Johnny's wife also claimed that her husband's handwriting was different from the one in the letter.

“The letter was written by someone else. The handwriting does not match that of my husband. It must have been written by someone who holds a grudge against us,” she said.

Meanwhile, Johnny's daughter claimed that she knew the culprit behind the threat.