This is very unusual. The Philippine government suspects a local terrorist group of plotting a major attack during the procession of the Black Nazarene, one of the country's major religious observances, and has come out with specific, detailed warnings about it.

AFP:

Philippine President Benigno Aquino said Sunday that authorities had discovered a plot by a terrorist group to disrupt a huge religious procession in Manila, and warned that members had not been arrested.

Aquino said police had been tracking the group, which he did not identify, that was allegedly planning to sow terror during the feast of the Black Nazarene on Monday, which annually gathers hundreds of thousands of devotees.

He did not elaborate on the nature of the threat, but said "there is a possibility of it" when asked if the plot involved bomb attacks.

"The sad reality of the world today is that terrorists want to disrupt the ability of the people to live their lives in the way they want to, including the freedom to worship and engage in community activities," Aquino said in a surprise news briefing.

"Your government will do what it has to do to ensure the safety and security of the public."

[...]

National police chief Nicanor Bartolome said he put Manila's 15,000-strong force on full alert to thwart any attacks by guarding the procession route, saying attendees should avoid bringing children and the elderly.

"Those with no important business in these areas are advised to postpone their trips for another day," Bartolome said.

Aquino's announcement came three days after the US government retained the Philippines in a list of countries labelled as "dangerous and unstable" in a fresh travel advisory for its citizens.

The cynical among us might see this warning as a way for the government to cover its behind if an attack occurs. But a specific warning to keep children and old people at home would seem to highlight the seriousness of the intelligence that led to the warning. It also shows authorities perhaps at their last extreme - going public as a way to try and deter the terrorists.

It wouldn't take much of a bomb to cause mass casualties when people are so close together. Let's hope the terrorists lose heart and back off, or the government is successful in interrupting the plot some other way.