Boston: Investigators told a House panel yesterday that the Boston Marathon bombs were triggered with the kind of radio-remote used for toy cars, leading some authorities to wonder whether Tamerlan Tsarnaev had instruction in more sophisticated bomb making. But the current working theory appears to be that the Tsarnaevs worked alone and learned bomb making on the Internet.

  Investigators are trying to unravel the past to see whether they missed a signal that could have prevented the Marathon bombings. The FBI had once been alerted by Russia that Tamerlan Tsarnaev had developed extreme religious views and they interviewed him in Boston. Tamerlan’s American born wife, who converted to Islam, is cooperating. The FBI is working with Russian investigators and has interviewed both parents of Tamerlan and Dzhokhar Tsarnaev. The young men’s mother told reporters in Russia she does not believe her sons were involved. “No, I don’t. And I won’t. Never.” She said, “America took my kids away from me.”

World: An eight-story garment factory building in Bangladesh collapsed, killing 228 and injuring more than 1,000 people. As many as 2,000 workers were in the building when it pancaked. The building had been ordered closed by authorities the day before after cracks developed in the walls, but the factory managers ignored the warning. People are still trapped in the rubble, begging to be saved.

National: The body of a Brown University student who had been falsely identified on the website Reddit as one of the Boston Marathon bombers, has been found in the Providence River. Sunil Tripathi, 22, disappeared March 16, a month before the Marathon. Reddit publishes “crowd sourced” content, which in this case was pure speculation by the online mob.

• All the living Presidents are together today for the dedication of the George W. Bush Library in Dallas. Presidential libraries are built with private money but operated by the National Archives.

Sandbagged: Floodwaters remain at or near their peak along the Mississippi and its major tributaries. Parts of Peoria, Ill., St. Louis and many small towns are under water. The floods are expected to start receding in the next few days, but more rain is coming.

Press: The website CareerCast has listed Newspaper Reporter as the worst job in America, just behind Lumberjack and Enlisted Military. Long hours, low pay and feeding the 24-hour news cycle were among the reasons given. It was always a lousy job unless you’re at the bar with a whiskey in your hand bragging about it to a blonde built like an hourglass.

-30-