KUALA LUMPUR, Malaysia — The Malaysian authorities released new details on Tuesday to buttress their conclusion that Flight 370 must have ended in a crash in a remote part of the Indian Ocean.

But with no physical evidence of the plane’s fate yet found, and the search suspended for a day because of treacherous weather, distraught relatives and friends of passengers mounted an angry protest in Beijing, breaking through police lines and marching to the Malaysian Embassy demanding more answers.

Hishammuddin Hussein, Malaysia’s defense minister and acting transportation minister, said at a news conference near Kuala Lumpur that the plane appeared to have sent one more partial signal eight minutes after the last of the previously disclosed electronic “handshakes” between the plane and a satellite, which engineers have analyzed to infer the plane’s probable path after it disappeared from radar screens early on March 8. Mr. Hishammuddin called the newly reported signal a “partial handshake.”