Viacom chief executive Philippe Dauman and board member George Abrams asked a Massachusetts court on Thursday to require an immediate medical exam of controlling shareholder Sumner Redstone.
In a filing with the Norfolk Probate and Family Court, Dauman and Abrams also asked for a court order requiring the 93-year-old Redstone to provide medical records relating to his mental condition for the past six years.
Redstone, who has trouble speaking and needs around-the-clock care, last month removed Dauman and board member George Abrams from the seven-person trust that will control Redstone’s majority ownership of media companies Viacom (viab) and CBS Corp (cbs) when he dies or is deemed incapacitated.
Get Data Sheet, Fortune’s technology newsletter.
Dauman and Abrams shot back with their own Massachusetts lawsuit contesting their removal from the trust and from the board of National Amusements, Redstone’s privately held movie theater company through which he owns 80 percent of the voting shares of Viacom and CBS.
In their suit, they claimed that Redstone is not mentally competent and has been manipulated by his daughter. Redstone has called that allegation “offensive and untrue” in court filings.
Dauman and Abrams on Thursday pointed to National Amusements’ move to replace Dauman and four other Viacom directors from the company’s board, adding that a medical exam was necessary because events impacting Redstone’s media empire “are unfolding at a quick pace, and are in danger of becoming irreversible.”
This Is What You Need to Know About the Sumner Redstone Trial
Those purporting to act on Redstone’s behalf “have orchestrated one of the most incredible and audacious corporate takeovers in the history of American business,” they wrote in a court filing.
A Redstone spokesman could not immediately be reached for comment on Thursday.