"alleged to support" is a correct and usable phrase in written English.
It is typically used to describe something that is claimed or believed to provide evidence or justification for something else. Here is an example: The statement made by the witness was alleged to support the defendant's innocence, but upon further investigation, it was found to be unreliable and unsubstantiated.
He was also alleged to have supported the passport application of a man linked to drugs.
The trio - Labour's deputy leader Harriet Harman, her husband, home affairs spokesman Jack Dromey, and former health secretary Patricia Hewitt - were alleged to have supported the Paedophile Information Exchange (PIE) during their time with the National Council for Civil Liberties NCCLL) in the 1970s and early 1980s.
Republican presidential candidates have linked the threat of terrorism from Isis to gun control since the San Bernardino shooting in December, in which 14 people were killed and 20 wounded by a couple alleged to have supported the militant group.
Iran is also alleged to be supporting the Houthis.
In some cases, the so-called shifta reported as killed were in fact members of the public, who were alleged to have supported the shifta.
His militia uses grenades on tomato vendors alleged to have supported a group of republican officers who, it must be said, have been wrongly described as plotting a coup when in fact they rose to the defense of the popular movement favoring the rule of law.
In Egypt (159th), after President Morsi's ousting by the army led by Al-Sisi, there has been a witchhunt against journalists alleged to have offered support to the Muslim Brotherhood.
60 Minutes Documents alleged to show Saudi support for some of the 9/11 hijackers; China's film industry; Schuyler Bailar, who may be the first openly transgender male athlete to compete in a NCAA Division I men's sport.
The US is alleged to have provided covert support for the 1973 coup by General Augusto Pinochet in Chile.
"Contributing to this decision were the recent arrests of six men in suburban Buffalo who are alleged to have provided material support to Al Qaeda," Mr. Ashcroft and Mr. Ridge said.
