HIGHLAND — Merri Loker’s late father Merle Berdine was in the Army on Dec. 7, 1941, sitting outside that Sunday morning when he heard planes overhead. The engines sounded different, and then Berdine saw the zeroes on the aircraft.

The Japanese were attacking Pearl Harbor.

76 years later, relatives of those who survived the sneak attack gathered Thursday at the Main Square Park gazebo to honor the memories of those who died and the survivors.

“This is a tradition,” said Loker, a Valparaiso resident. “It’s a memorial to those who died in the attack and those who died afterward.”

Loker, who attended the 75-year anniversary last year in Hawaii, noted the ceremony was “very humbling” and considerably warmer than the 25-degree temperature for Thursday's midday service.

Sponsored by the Sons and Daughters of Pearl Harbor Survivors, the program began at 11:55 a.m., when, in Indiana time, Imperial Japanese forces attacked Pearl Harbor, a natural deep water naval port and home to the U.S. Navy’s Pacific Fleet.

In under two hours, the surprise attack resulted in 2,403 U.S. service personnel killed, most of those naval personnel and many of them aboard the USS Arizona, a battleship which exploded when a bomb hit the ammunition room.

Another 1,143 U.S. soldiers were wounded, while 68 civilians died and 35 were wounded in the attack. Twenty U.S. ships were either sunk or damaged.

Although Japanese officials intended to neutralize U.S. forces, allowing Japan to dominate the Asia Pacific region, the attack drove the U.S. into World War II, creating a global conflict.

“This attack, which was supposed to unleash a devastating blow to American morale, accomplished just the opposite,” said James M. Laud, District 5 director for the Sons and Daughters of Pearl Harbor Survivors. “This surprise and unprovoked attack on the U.S. shocked and enraged the previously divided American people into a level of purposeful unity hardly seen before or since.”

Even today, Laud said, Pearl Harbor teaches two key lessons: to be ever alert and to remember, as Lincoln said in his Gettysburg Address, “those who died shall not have died in vain.’

Joseph Moore Sr., of Crown Point, attended with son Joe to honor Joseph Moore Sr.'s late father, a Pearl Harbor survivor, as a “tribute to my father and his longevity in the service.”

Although exact numbers are difficult to pin down, Laud estimates there are five remaining Pearl Harbor survivors in Indiana and perhaps 400 overall.

Laud announced the names of Pearl Harbor survivors who died in the past year. Meeting these veterans and then learning of their deaths, Laud said, “It gets tougher every year.”