A document given to British authorities allegedly confirms Muslim Brotherhood financial support for terrorist groups, including the ISIS Sinai Province affiliate, Egypt Today reported.

But this alleged connection between ISIS Sinai Province and the Muslim Brotherhood should be taken with a grain of salt, Hudson Institute Senior Fellow Samuel Tadros told the Investigative Project on Terrorism.

"There is no evidence of an ISIS connection to the Muslim Brotherhood. We don't know that at all. It doesn't make sense. Ansar Bayt al-Maqdis, the pre-ISIS organization, condemned the Muslim Brotherhood while they were still in power," Tadros said.

ISIS Sinai is a tribal Sinai-focused phenomenon. It mistrusts people from the Nile Valley, where most Egyptians live, and came under tight control of the ISIS leadership in Iraq and Syria, Tadros said. He dismissed former Egyptian security official Khaled Okasha, who has been a source of much of the effort to connect ISIS Sinai and the Muslim Brotherhood in the Egyptian press as a "nutcase."

But British authorities last week designated two other groups mentioned in the report, Liwa al-Thawra and Hassm, as terrorist organizations based on an analysis of attacks against Egyptian security personnel and public figures, the British Embassy in Cairo announced last Friday.

The connection between Liwa al-Thawra, Hassm and the Muslim Brotherhood is independently verifiable and undeniable, Tadros said.

Liwa al-Thawra and Hassm reportedly evolved from a network of terror cells established by late Muslim Brotherhood Guidance Bureau member Mohamed Kamal, who was killed in a shootout with Egyptian security forces last year. Liwa al-Thawra eulogized Kamal after his death and then assassinated Egyptian Army Brigadier-General Adel Regai Ismail in retaliation for Kamal's death. Hassm congratulated Ismail's killers.

Hassm claimed responsibility for an October attack against Myanmar's embassy in Cairo.

Hassm appears to have evolved from the Revolutionary Punishment Movement (RPM), Brotherhood researcher Mokhtar Awad, noted in an Oct. 3, 2016 Atlantic Council article. RPM has attacked police and military targets and received support on social media from American pro-Brotherhood activists. Hassm's justifications for its terror attacks are similar to those found in The Jurisprudence of Popular Resistance to the Coup, a book written by Islamic scholars close to the Muslim Brotherhood.

Connections between Liwa al-Thawra, Hassm and the Muslim Brotherhood should be further investigated and taken into account in deciding whether the Egyptian Brotherhood should be classified as a terrorist group.