While Hamas has claimed to have taken at least 163 hostages out of Israel into Gaza during the weekend terrorist attacks, there is visual evidence for at least 64 of them being held captive, The Washington Post reported Thursday.

Of those 64, analysis shows that 49 are civilians, including nine children; 11 are members of the Israeli military; and four are of unknown status.

The nationality of the hostages cannot be confirmed by the analysis, but National Security Council spokesman John Kirby has told U.S. press that 27 Americans have been killed in the war over the past six days, and that 14 known Americans are missing.

The visual evidence sets a bottom-line number for hostage totals, because it accounts for only those verified by direct visual proof, according to the Post.

The analysis comes after Hamas reportedly vowed to broadcast the execution of a hostage for every military strike on Gaza. There have been numerous strikes on Gaza, but thus far no known executions, although that does not mean they haven't happened.

Israeli airstrikes have killed at least four Hamas-held hostages thus far, Hamas terrorists have claimed, with the reports suggesting the deaths were a result of a strike and not a retaliatory execution.

There is video evidence of Hamas terrorists having captured 106 people in Israel during Saturday's terrorist attack, with at least 26 behind held locations that cannot be verified, in addition to at least 16 seen only in Israel and whose ultimate fate therefore remains unknown, said the Post.

Israel has estimated that between 100 and 150 people have been taken hostage, while Hamas is reportedly saying they are holding "tens" of people, the Post reported.

The Post analysis comes from videos and images posted on social media since the terrorist attack, with geolocation data or background buildings or locations, along with family member confirmations, verifying the identity of captives held in Gaza.

The hostage attacks occurred in a 20-mile wide territory from the Nir Oz village in the south to the main Erez border crossing in the north, showing the Hamas attack came from nearly the entire Gaza border with southern Israel.

This is the largest hostage-taking terrorist operation between Israel and the Arab world since 1973, according to the Post.

A German mother made a second desperate appeal for the German government to help find her daughter Shani Louk on Tuesday, after video emerged that appeared to show her daughter in the captivity of militants in Gaza.

"I am the mother of the abducted Shani Louk," she said in a video obtained by Reuters. "We now have more information that Shani is alive but has a severe head injury and is in critical condition. Every minute is critical. And we ask, no, we demand that the German government act quickly. One should not argue about questions of competence. One must act quickly to get Shani out of the Gaza Strip. This is really my desperate appeal to the whole country of Germany to help me get my Shani back home in good health. Thank you."

Shani Louk, a German-Israeli dual national in her 20s, is among those missing after Hamas fighters rampaged through Israeli towns on Saturday morning.

Her cousin confirmed to the Post that Shani Louk was at a dance party that was attacked by militants during the raid.

A graphic and disturbing video emerged over the weekend showing a woman matching Louk's appearance motionless and semi-naked on the back of a pickup truck. She is surrounded by armed men chanting "Allahu Akbar" and one man is seen spitting on her head.

Information from Reuters was used in this report.

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