Security will be tightened at cities across the country on Tuesday in response to the attack on the Boston Marathon, a lawmaker on the House Intelligence Committee said.

Rep. Dutch Ruppersberger (D-Md.), the intelligence panel’s ranking Democrats, said law enforcement officials will be sweeping major urban areas for explosives.

"Local, state and federal law enforcement are putting most urban cities on high alert because we want to make sure this is not a pattern like 9/11, so you're going to see law enforcement and dogs who can sniff out explosives in a lot of areas throughout the country — especially here in Washington D.C — whether it be in train stations, ports, federal buildings, especially the Capitol and this area," said Ruppersberger to reporters Monday evening.  

Ruppersberger was briefed on the attack in Boston Monday by James Clapper, the director of national intelligence. The lawmaker said he expected to get a more detailed briefing from the FBI and the Department of Homeland Security (DHS) on Tuesday during the intelligence committee's weekly briefing.

Ruppersberger was hesitant to label the bombings a terrorist attack, saying that he needed more information from investigators before characterizing it that way.

"Terrorist groups are never going to win the war, but they want to win the battle and they want to disrupt our country and our way of life. They want to create an incident. Well, they've done that," he said.

"They made a statement and unfortunately Americans were killed or injured because of that. We're going to do whatever we can to bring these people to justice."

"It was an attack. We'll define what it is or isn't after tomorrow."