NEW DELHI, Jan 23 : West Bengal chief minister Mamata Banerjee on Tuesday targeted the BJP-ruled central government for not keeping their promise of investigating disappearance of Netaji Subhas Chandra Bose.

"It's India's bad luck that even after so many years we do not have Netaji's death date. We do not know what happened to him. It's a shame," Mamata said on Netaji's 127th birth anniversary.

"BJP promised to investigate Netaji's disappearance before coming to power but forgot after that. For 20 years, I tried to make Netaji's birth anniversary a national holiday but failed; please forgive me," she said.

In an apparent reference to the Centre declaring a half-day holiday in central government offices for Ram temple's consecration ceremony on Monday, Banerjee said these days holidays are declared for political advertisements, but nothing is announced for those who gave up their lives fighting for the country's freedom.