The Biden administration believes six US citizens are still being held hostage in Gaza, but it has limited knowledge of their conditions and does not know whether all are still alive, a senior administration official told NBC News on Tuesday. The administration lowered the number of Americans it has said are unaccounted-for from eight to six after the IDF confirmed the deaths of Gad and Judi Haggai , two US-Israeli citizens, in recent weeks. The US had previously thought they were being held in Gaza, but now, according to the White House, officials believe they were murdered by Hamas on October 7 and their bodies are being held in Gaza. When the war started, about a dozen Americans were considered unaccounted-for, but the Biden administration was unclear about how many were alive and being held hostage, noted NBC News . In the initial weeks of the war, Judith and Natalie Raanan became the first US citizens to be freed from Hamas captivity. Two more Americans — Abigail Mor Idan , 4, and Liat Beinin , 49 — were freed in November in a deal in which women and children hostages were released. Senior US officials continue to push for another temporary truce and hostage deal, but there is limited optimism, because Israel and Hamas remain far apart on critical questions such as who would be eligible for release, a Biden administration official told NBC News . Israel and Hamas in recent days have resumed indirect negotiations on another deal, but no progress has been recorded yet. On Monday, it was reported that Hamas forwarded to Israel, through the Egyptian and Qatari mediators, a proposal for the release of hostages which includes an Israeli withdrawal from the Gaza Strip. Israel rejected the proposal. Related articles: 'Netanyahu didn't tell us anything new' 'We won't have a funeral until his body is returned' 'I won't leave anyone behind' Brother of kidnapped soldier sends message to Belgian FM On Tuesday, Prime Minister Benjamin Netanyahu met with families of the hostages held in Gaza by the Hamas terrorist organization. "The effort [to return the hostages] continues, the contacts are taking place, they have not been cut off," Netanyahu assured them, adding, "There was an ultimatum from Hamas, now it has softened a bit."