MONHEGAN, Maine — The big wave that swept Thomas Clarke off a Monhegan Island ledge and to his death in the Atlantic Ocean on Friday afternoon likely arrived with little warning, according to a volunteer firefighter who helped with rescue efforts that day.

Clarke, 32, from Dublin, Ireland, was on Monhegan to attend a wedding. He and five friends had been hiking along the southeast shore of the island, located 10 miles out to sea, and were exploring Gull Rock Ledge when a swell from Hurricane Katia knocked him into the water.

“There’s very deep water on that side of the island, and you can’t see a big wave coming,” Jessica Stevens of the Monhegan Volunteer Fire Department said Sunday. “They were not going to see the big waves from Hurricane Katia. They were enjoying the edges of the sea and hiking.”

The Coast Guard suspended its 34-hour search for Clarke on Saturday evening, after crews on vessels and aircraft scoured nearly 200 square miles looking for him.

“It’s incredibly sad,” Stevens said. “It’s a good lesson for all that the sea is to be respected.”

Commander Brian Gilda of Coast Guard Sector Northern New England said in a press release that the support during the search from the community and the Maine Marine Patrol was “tremendous.”

“Unfortunately, this assistance did not achieve the outcome everyone had hoped for,” he said.

After Clarke disappeared into the ocean, four of the friends were trapped in a shallow cave on the ledge. A fifth friend was able to run for help, Stevens said. Previous reports that four friends swam about 300 yards to Gull Rock in an attempt to rescue Clarke were incorrect, she said.

When the firefighters’ pages went off that afternoon after the emergency was sounded, they raced to help.

Two of the firefighters jumped into boats and began to search the water for Clarke, assisted by a good Samaritan in a kayak. Others went to Gull Rock, where the four trapped friends spent between two and three hours before they were able to escape.

Stevens said that she helped to keep an eye on the four in the cave.

“We were waiting for the tide to drop to its lowest point in hopes that the swell and waves coming in would be smaller,” she said “and the ledge they had come in on would be a less dangerous place.”

The volunteer rescuers kept in verbal communication with the trapped group, she said.

She said that two more friends from the wedding party eventually joined the group in the cave and helped three of them to climb out.

“In general, it’s not good to add individuals to a group that’s stuck,” Stevens said. “I wouldn’t advise it. But every situation is different. Sometimes having someone who wasn’t part of the scary situation [helps].”

The fourth person, a woman, needed more help. She was airlifted to safety by a Coast Guard Jayhawk helicopter from Air Station Cape Cod. A rescue swimmer was dropped from the helicopter and picked her up, Stevens said.

According to the firefighter, someone involved with the wedding has a connection to Monhegan. The wedding was held on Saturday as planned.

She said that it is far from the first time that a person has been swept out to sea, although it is the first such occurrence in at least 20 years.

Last year, a person was swept out to sea by a big wave generated by a hurricane, but people in a boat were able to rescue him, she said.

“I know that in the history of Monhegan, some people were swept out to sea and have never been found,” she said.

The island library originally was named for two children who had suffered that fate in 1926. According to the history of the Monhegan Memorial Library, 11-year-old Jackie Barstow was celebrating her birthday on Aug. 8 with a picnic on a flat ledge at the base of Black Head when a large wave suddenly came ashore. It also was churned up by a hurricane.

“The other children watched in horror as they saw Jackie enveloped by a huge wave and washed into the swirling waters of Squeaker Cove — scene of many a shipwreck,” Alta Ashley wrote in a 2008 history of the library.

Edward Vaughan, 15, was a strong swimmer and jumped into the surf to save her. He was able to catch her belt and lift them both onto the rocks, but a second large wave pulled them back into the ocean, where they disappeared into the undertow.

Grieving islanders and summer residents established the Jackie and Edward children’s library as a memorial, according to the history.

According to a press release issued Saturday by the Coast Guard, people caught in a rip current should remain calm and swim parallel to the shore.

“If you can’t reach shore, float or tread water until you are out of the current,” it stated. “We also recommend that, whenever possible, wear a life jacket while on the water and never swim alone.”