By Richard Benedetto, USA TODAY

PANAMA CITY — President Bush strongly defended U.S. interrogation practices for detainees held in the war on terrorism Monday, insisting, "We do not torture."

On the final day of a three-nation Latin America trip, Bush said at a news conference that he will not relent in battling terrorists. "There's an enemy that lurks and plots and plans and wants to hurt America again," he said. "So you bet we will aggressively pursue them, but we will do so under the law."

Bush was asked to respond to reports, first published in The Washington Post, that the United States maintains secret prisons in Europe and Asia for terrorism suspects. The president didn't acknowledge that they exist.

U.S. interrogation practices have been under fire since news accounts in 2004 reported harsh tactics by U.S. interrogators at Abu Ghraib prison in Iraq, Guantanamo Bay in Cuba and at detention facilities in Afghanistan. In a new case Monday, five Army Rangers were charged with abusing detainees in Iraq.

The administration has said in a statement that while it does not condone torture, it opposes the measure because it would be "unnecessary or duplicative" and could restrict "the president's ability to conduct the war (on terrorism) effectively under existing law."

The House of Representatives has not voted on a similar measure, but Rep. John Murtha, D-Pa., has said he intends to introduce one and predicted it would pass "overwhelmingly."

Sen. Edward Kennedy, D-Mass., said Monday that Bush's comments and Cheney's lobbying effort "only demonstrate that the White House learned nothing from Abu Ghraib and Guantanamo." Kennedy said that the administration's "legal justifications for harsh techniques ... only make the war on terrorism harder to win and put our soldiers in further danger."

Bush said Congress and the White House have an obligation to protect the American people. "And we are aggressively doing that," he said. "We are finding terrorists and bringing them to justice. We are gathering information about where the terrorists may be hiding. We are trying to disrupt their plots and plans."

Also Monday, the Supreme Court agreed to hear a challenge to the administration's practice of trying foreign terrorism suspects in military tribunals, which bypass traditional U.S. courts. The case, which won't be decided for months, is a key test of Bush's presidential wartime powers.

Bush spoke at a news conference with Panamanian President Martin Torrijos.