Two of them are from California originally, one from Berkeley and another from Fresno.
[Ads /]
And on Tuesday, they're calling on the U.S. government for help.
"The first one said 'I love you.' And immediately, at 8:11, also, it said 'I'm sorry,'" Rachel Goldberg, the mother of Hersh Goldberg-Polin said.
Those were the last texts Rachel Goldberg got from her son, 23-year-old Hersh Goldberg-Polin, an Israeli American from Berkeley, Saturday morning, shortly after the first bomb sirens went off in Jerusalem.
MORE: '9/11 of the Israelis': Bay Area Jewish community reacts to Hamas attacks, kidnappings
'9/11 of the Israelis': Bay Area Jewish community reacts to attacks
But later, the family learned Hersh was in a bomb shelter that was attacked.
"They were all civilians at a music festival and they were fish in a barrel, sitting in this bomb shelter, terrorists came to the door, they were throwing grenades in, shooting machine guns and we know that Hersh's arm from the elbow down, was severed," Goldberg said.
Goldberg says she was told Hersh put together a makeshift tourniquet using his shirt and Hamas came in after the gunfire settled down, asking anyone who could walk to come with them, taking Hersh and five others away in a pickup truck.
Police told his parents, that his last known cellphone signal was on the border with Gaza.
[Ads /]
"By eyewitness accounts, from the people that we talked to who were in this bomb shelter, several people independent of each other said you son and his friend Amir saved our lives, because as grenades were being thrown in, they were tossing them back out, they were trying to comfort people," Jon Polin, Hersh's father said.
MORE:14 Americans killed in Israel, others being held hostage by Hamas: President Joe Biden
Adrienne Neta, 66, from Fresno is also missing.
The mother of four and grandmother of seven is believed to have been taken by Hamas to the Gaza Strip.
Three of her kids believe they heard it happen over the phone.
"Both my brother and my sister were on the call with her as the terrorists barged into her home and we heard a bit of screaming and that was our last contact with her," Nahar Neta, one of Neta's sons said. "The optimistic scenario here is that she's held hostage, in Gaza and not dead in the street."
With few answers on how to find her, they're now calling on the U.S. government for help.
"I want to also speak about the responsibility that the U.S. administration, President Biden and the Secretary of State Blinken has for the lives of every U.S. citizen that it is out there and they're responsible to bring the U.S. citizens back home safe and sound, we expect nothing less from the U.S. administration," Neta said.
On Tuesday, President Biden said at least 14 Americans have been killed in the Hamas terrorist attacks in Israel, he said in an address.
He condemned Hamas' incursion as an "act of sheer evil."
Biden also confirmed that American citizens are among those being held by Hamas.
He said he's directed his "team to share intelligence and deploy additional experts from across the United States government to consult with and advise Israeli counterparts on hostage recovery efforts."
The U.S. has started reaching out to the families of Americans missing in Israel as part of its efforts to identify the U.S. citizens who may be among the hostages taken to Gaza by Hamas, according to an official.
Biden also said in his address, "We stand with Israel. And we will make sure Israel has what it needs to take care of its citizens -- defend itself and respond to this attack."
[Ads /]
MORE: SF civic leader, business owner describes frightening scenes in Israel: INTERVIEW
SF civic leader, business owner describes frightening scenes in Israel: INTERVIEW
Dan Cohen, a longtime former Oakland resident now living in Israel working in communications, said first and foremost, the families are seeking information.
"The United States is still the only superpower in the world that has the ability to do things that frankly, individuals here in Israel and even Israel may not be able to do so I think what they're trying to do is get more information and get the administration to step in," Cohen said.
President Biden issued a statement Monday saying:
"While we are still working to confirm, we believe it is likely that American citizens may be among those being held by Hamas. I have directed my team to work with their Israeli counterparts on every aspect of the hostage crisis, including sharing intelligence and deploying experts from across the United States government to consult with and advise Israeli counterparts on hostage recovery efforts."
In California, there was a march in support of Israel being held on Tuesday evening, sponsored by a number of Jewish congregations.