"Cancer has spread throughout the BJP, which has to be removed," BJP parliamentarian from Bihar, Bhola Singh told NDTV.

Bhola Singh, a BJP parliamentarian from Bihar, has slammed Prime Minister Narendra Modi and BJP chief Amit Shah for the party's massive defeat in the assembly elections in the state, saying Mr Shah must explain or step down."The top leadership alone, which took all the decisions, has to take responsibility for defeat," Mr Singh, the lawmaker from Begusarai, told NDTV in an exclusive interview. "They must explain the reasons for the defeat to the party and if it's not accepted, they must go," the 76-year-old said.Amit Shah is due for a second term as party president later this year."Who is Amit Shah? He and the PM are who they are because we entrusted them with all our power," said Mr Singh who, just two days ago, launched a blistering attack on the Prime Minister and other leaders, saying they made unseemly comments during campaigning in Bihar."Cancer has spread throughout the BJP, which has to be removed," Mr Singh added.He listed several reasons for the Bihar loss, but singled out Rashtriya Swayamsevak Sangh (RSS) chief Mohan Bhagwat's statement on caste reservations in the run-up to the elections."It's wrong to say the RSS chief's statement didn't have any impact. It was like a hailstorm on BJP's prospects," Mr Singh said.He also did not spare the PM, saying he "came down to the level of local leaders in the Bihar campaign." "He attacked Lalu and his daughter, then even Nitish's DNA. What was the need for the PM to make such statements? Amit Shah's comments on Pakistan also caused a lot of damage," Bhola Singh said.Mr Singh's remarks follow a joint statement by BJP veterans, including LK Advani, Murli Manohar Joshi and Arun Shourie, where they alleged that the party had been "forced to kow-tow to a handful, and how its consensual character has been destroyed." Bhola Singh said that he fully agreed with that statement.Senior BJP leaders have reportedly asked the two-time parliamentarian to exercise restraint. "But I am not afraid of any action by the party," Mr Singh said.