Malaysia’s ruling Barisan Nasional coalition was reeling with heavy losses midway through counting following Wednesday’s general election, with four top lieutenants of Prime Minister Najib Razak – including transport minister Liow Tiong Lai and health minister S. Subramaniam – among those felled so far.

The surprises came as both Najib and opposition leader Mahathir Mohamad won their seats.

Mahathir’s victory means regardless of the final result, the 92-year-old is set to re-enter parliament 15 years after stepping down from a 22-year tenure as prime minister.

“Swing seats are up for grabs [and] the opposition should feel confident because of an overall downward voting trend for BN,” said Rashaad Ali, a Malaysian politics observer at Singapore’s S. Rajaratnam School of International Studies.