The Fukushima No. 1 nuclear plant, whose 2011 triple-meltdown forced the relocation of 160,000 people, may provide a new blueprint for terrorists seeking to inflict mass disruption, security analysts said Monday at a meeting of the International Atomic Energy Agency.

The U.N. atomic agency convened a weeklong meeting of 1,300 diplomats, scientists and security analysts in Vienna to examine ways to boost protection against nuclear terrorism. The meeting is the IAEA's first ministerial conference.

"Fukushima sent a message to terrorists that if you manage to cause a nuclear power plant to melt down, that really causes major panic and disruption in a society," Matthew Bunn, a Harvard University professor and former White House adviser, said at a briefing. "All you need to do is cut off the power for an extended period of time."