Indian and Pakistani officials signed an agreement Wednesday to avert the risk of accidentally triggering a nuclear war between the South Asian rivals. The signing, done in New Delhi in the presence of the foreign ministers of both countries, comes just days after a pair of blasts set off a fire that killed 68 people on a train to Pakistan. The blast has been seen by officials from both countries as a way to divert them from the peace process. Details of the pact have been kept secret, but it includes confidence-building measures related to both countries' nuclear arsenals, officials say, part of continuing peace efforts after more than a half-century of hostility. India and Pakistan tested nuclear weapons in 1998, and have been pursuing peace initiatives since 2004.