WASHINGTON--The Navy yesterday dispatched a second aircraft carrier to sea in the Mediterranean, but sources said the Pentagon had yet to order a military strike against Libya in retaliation for recent terrorist attacks.

Should such orders be issued, however, the Navy is in position to form a two-carrier battle group that would include 16 combat ships and more than 160 airplanes, the sources said. It would take about two days to move such a battle group to the Libyan coast, said the sources, who would speak only on condition of anonymity.

The Pentagon officially declined comment on the position of the Navy ships. But officials who requested anonymity said the carrier Coral Sea--its orders to return home canceled--had departed port in Malaga, Spain, early yesterday.

Meanwhile, NATO commander Bernard Rogers said yesterday there is "indisputable evidence" at least one fatal bombing was the work of a terrorist network set up by the Libyan strongman.

The supreme allied military commander in Europe said a West Berlin nightclub explosion, which killed an American sergeant and wounded 50 other servicemen, was the work of a "worldwide network" of terrorists set up by Khadafy.

"I can't tell you how we get it, but the evidence is there," Rogers told an audience in Atlanta.

The general said U.S. officials learned of the impending attack on Saturday and were trying to warn off-duty soldiers at gathering spots in West Berlin when the blast occurred at the La Belle club.

While Reagan on Wednesday night declined to blame Khadafy outright for the bombings at the discotheque and aboard a TWA jetliner over Greece, he said that "We're gathering evidence as fast as we can."

Before his nationally broadcast news conference, Reagan told a group of editors that Khadafy "is definitely a suspect" in the two fatal bombings.

But he said, "We're continuing with our intelligence work and gathering evidence on these most recent attacks, and we're not ready yet to speak on that."

Nor is Reagan ready to order the two carriers in the Mediterranean to reform a battle group and head for stations off the Libyan coast, Pentagon sources said yesterday.

Britain's Lord Carrington, the secretary-general of NATO, said yesterday, "I don't think the United States can sit back and allow this sort of terrorism without taking some sort of retaliatory action."

"What it would be, I don't know," Carrington said on NBC's "Today" show. "I don't think you could say anything the United States would do would be supported by the Europeans. But I can tell you there would be a very great deal of sympathy and support for the United States for doing something."