Seidu Oshiomhole, the younger brother of the National Chairman of the All Progressives Congress, Adams Oshiomhole was beaten up by suspected thugs on Tuesday.
Seidu is also the lawmaker-elect for Etsako West 11 to the Edo State House of Assembly.
The attack on Oshiomhole and 14 other lawmakers of the Edo State House of Assembly is the latest in the crisis between the Edo State Governor, Godwin Obaseki, and the National Chairman of the APC.
15 lawmakers, who were absent at midnight on Monday when the other nine members of the Assembly were inaugurated, were attacked at a hotel in downtown Benin, the Edo State capital, where they were having a meeting.
Some of the lawmakers attacked by the suspected thugs were said to have sustained serious injuries.
A former Deputy Speaker of the Assembly, Victor Tiger Edoror, was said to have led his colleagues to the police headquarters in Benin to report the assault.
The nine members who met to inaugurate the Assembly elected Frank Okiye (Esan North East 1) as the Speaker.