The yacht was hijacked last Friday off the coast of Oman. Later that same day, a U.S. Navy warship began tracking the yacht as it made its way toward the Somali coast. The U.S. even make radio contact and began a negotiation process with the pirates.
Over the weekend, President Barack Obama authorized the use of force against the pirates if necessary.
On Monday, two pirates even boarded the warship, USS Sterett to continue negotiations and ended up spending the night aboard.
However on Tuesday, a rocket-propelled grenade was fired from the yacht at the USS Sterett which was 600 yards away. Then, gunshots were heard inside the yacht's cabin, and the Navy moved in.
"The U.S. sailors discovered that all four had been shot by their captors. Despite immediate life saving maneuvers, they were dead," said Vice Adm. Mark Fox, commander of U.S. naval forces for Central Command.
About 4,000 Southern Californian Marines and sailors were dispatched to international waters to fight piracy Tuesday. Three San Diego-based warships steamed out of port Tuesday, part of Camp Pendleton's 13th Marine Expeditionary Unit. Their mission will be to provide humanitarian aid, support operations overseas, and combat piracy. The military service members will be gone for seven months.
Two of the Americans were from Southern California. Scott and Jean Adam from Marina del Rey have been sailing around the world since 2004 distributing bibles.
The Adams were parishioners at the St. Monica Catholic Church in Santa Monica. It was a somber morning mass at the church on Tuesday as parishioners honored two of their own.
"I'm extremely emotional about it, because it seems so senseless," said parishioner Evonne McClure.
"They decided in their retirement that they wanted to do something to make a difference in this world. That's at the heart of this community, is to send people to make that difference in this world, and that's what they wanted to do, so they chose this very unique mission," said Monsignor Lloyd Torgerson, St. Monica's Catholic Church.
"All of us at Del Rey Yacht Club are devastated by this horrific event that has occurred," said Commodore Gary Deitsch, Del Rey Yacht Club.
The Adams' decision to travel the world to share their faith was documented on their website svquest.com.
On their most recent journey, they were joined by a Washington state couple, Bob Riggle and Phyllis Maccay. The two from Seattle joined the Adams on the yacht, the Quest.
U.S. forces said they heard gunshots aboard the yacht on Tuesday and responded. When they boarded the Quest, they discovered that all four hostages had been shot and killed by the pirates.
During the confrontation, two pirates died and 15 were captured and detained. The U.S. forces also found the remains of two other pirates already dead aboard the Quest. In total, it is believed that 19 pirates were involved in the hijacking of the yacht.
A family member of one of the slain hostages spoke to the media after the killing.
"She has a ton of friends and family. Our family is big. Our family is close. We love her and we are devastated," said Nina Crossland, Phyllis Maccay's niece.
The question for some remains: Why would experienced sailors such as the Adams head for such dangerous waters?
"I like adventure, but I like to come out alive," said sailor Hanna Hartnell.
"He had a strong desire to sail his own boat around the world. Jean was having a very difficult time with the heat of the tropics and wanted to get to European waters," said Scott Stolnitz, a friend of the Adams.
At the church, many said they admire the Adams' desire to spread the word of God.
"We pray especially for their family, for those who loved them most in this world, we ask you Lord to bless them," Torgerson prayed.
Torgerson said that two of Jean Adam's adult children from a previous marriage are members of the church and he will be consulting with them about a future memorial service.