WASHINGTON—An officer died after being stabbed Tuesday during a burst of violence at a transit station outside the Pentagon, and a suspect in the incident was shot by law enforcement and died at the scene, officials said. The Pentagon, the headquarters of the U.S. military, was temporarily placed on lockdown after gunshots were fired Tuesday…

NEW YORK—Hackers infiltrated computer systems for the Metropolitan Transportation Authority in New York, setting off a scramble to counter a potentially crippling cyberattack against North America’s largest transit system, MTA officials confirmed on Wednesday. The officials said in a statement that the agency received an alert from the FBI and other federal agencies saying three…

MEXICO CITY—An elevated section of the Mexico City metro collapsed and sent a subway car plunging toward a busy boulevard late Monday, killing at least 23 people and injuring about 70, city officials said. Rescuers initially searched a car left dangling from the overpass for anyone who might be trapped. Those efforts were suspended early…