Prashant Koshor's tweet came after no NDA leader went to receive the solider's body at the airport.
Election strategist Prashant Kishor, who joined Bihar Chief Minister Nitish Kumar's party last year, apologised on his party's behalf after the state government and Prime Minister Narendra Modi came under sharp political attack from the opposition because no senior leader from their parties went to receive the body of a solider who died in an encounter in Jammu and Kashmir.
"We are sorry for the error of judgement on part of those of us who should have been there with you in this hour of grief," Prashant Kishor said in a tweet on Sunday.
Pintu Singh, a Central Reserve Police Force (CRPF) solider from Bihar's Begusarai district, was killed in an anti-terror operation in Jammu and Kashmir's Kupwara on Friday. His body, draped in tricolor, had arrived at the Patna airport at 8.30 on Sunday morning. Three hours later, Chief Minister Nitish Kumar, accompanied by several cabinet colleagues, had gone to the airport to welcome PM Modi for a huge rally of the ruling National Democratic Alliance (NDA) in Patna.
Bihar's opposition leader Tejashwi Yadav attacked the ruling alliance over the issue.
"Ministers are only concerned about remaining in power. It shows how concerned they are about the soldiers. NDA leaders were more concern about Sankalp rally of (Prime Minister) Narendra Modi. They have neglected to pay homage to a brave soldier who was killed for the country," Pintu Singh's father Chakradhar Singh said.
Among those who came to pay their respects to the CRPF inspector, was Lok Janshakti Party parliamentarian Choudhary Mahboob Ali Kaiser and state Congress chief Madan Mohan Jha.
PM Modi and Nitish Kumar shared a political platform after a decade for the Sankalp rally at the Gandhi Maidan in Patna ahead of the national election.
The opposition has been attacking the government for "blatant politicisation of the sacrifices of the armed forces" since the Pulwama terror attack.