If, as rumored in Kuala Lumpur, Prime Minister Najib Razak intends to sack another seven United Malays National Organization leaders from the party, he is taking a daring gamble. They include Kedah Chief Minister Mukhriz Mahathir and former Deputy Prime Minister Muhyiddin Yassin.

But both Mukhriz, the son of former Prime Minister Mahathir Mohamad, and Muhyiddin hail from the Malay heartland, UMNO strongholds whose support he needs to remain in power. Officials in Johor, where UMNO was born in the 1950s, have already warned that Najib’s dismissal of Muhyiddin as deputy prime minister would wreck the party’s southern power base in 2018.

“He is trying to surgically remove all opposition from the party,” said a longtime political observer in Kuala Lumpur. He and other observers speculated that the prime minister’s wife, Rosmah Mansor, is behind the drive to rid the party of figures questioning Najib’s stewardship of the disastrously managed 1Malaysia Development Bhd., although there is no particular proof of that.

Najib has already fired Attorney General Abdul Gani Patail, who was said to be preparing charges against him, as well as the head of the police special branch unit and sent two top officials of the Malaysian Anti-Corruption Commission on “vacation.”

Officials have also ordered the arrest and questioning of a half-dozen MACC officials on suspicion they were leaking details of the case against the prime minister. A parliamentary investigation has been halted as well as the MACC probe.

But while he has gone to extraordinary effort to contain the scandal, it has spread well beyond Malaysia’s borders, with Swiss authorities saying on September 2 that they had frozen funds in Swiss banks amid a probe into people linked to 1MDB, on suspicion of corruption and money laundering. Singapore has already frozen funds despite a private plea from Najib, who reportedly flew to the lion city in August.

The entire country was already deeply embarrassed this week by a massive rally that drew tens of thousands of protesters -- one of whom was former PM Mahathir, who is now being investigated for criminal defamation concerning his remarks at the Bersih 4.0 demonstration over the weekend and calling for Najib’s resignation.

In addition, Transparency International President Jose Ugaz and 1,000 delegates to the 16th International Anti-Corruption Conference at the government center Putrajaya called attention to corruption allegations involving a US$680 million “donation” to Najib Razak’s personal banking accounts – who paid the money, why and what happened to it. Najib has not come up with any convincing explanation for the funds, deposited in his account in March of 2013.

The premier’s peril over the threatened new round of firing stems from the fact that by and large, all of the officials he has sacked are in Putrajaya, the seat of government. Najib has been able to keep the Malay heartland behind him by alleging foreign plots, ethnic Chinese attempts to curb Malay political power and Mahathir, who supposedly wants his son to take Najib’s place.

But Kedah, where Mukhriz remains extremely popular, and Johor, where the sultan met Muhyiddin in a show of support after he was pushed as deputy prime minister, are two areas that are crucial to electoral success for UMNO.

In addition to Mukhriz and Muhyiddin, others scheduled to be ousted are party vice-president Mohd Shafie Apdal, who is equally popular in Sabah, a largely Christian or tribal region in East Malaysia which UMNO found critical to maintain itself in power in the 2013 general election. Others are MPs Aziz Sheikh Fadzir and Jumat Idris and former Terengganu chief minister Ahmad Said, all of whom are local politicians with electoral followings.

Earlier, officials ordered the expulsion of Anina Saadudin, a Langkawi women’s wing delegate who caused a storm with an impassioned rant saying the prime minister was urinating on the heads of the 3 million party rank and file. A YouTube video of the young woman’s tirade went viral and was seen by tens of thousands of people.

Mukhriz told the independent news website Malaysiakini he hasn’t heard of any action ousting the seven. However, recently in the city of Alor Setar in Mukhriz’s home state, Najib is said to have told an UMNO division meeting that it was okay to undermine Mukhriz because Mukhriz “had it easy,” referring to his appointment as chief minister – that he put Mukhriz in and that the former prime minister’s son should toe the line on the controversies surrounding 1MDB, the unpopular goods and services tax, an 18–month postponement of UMNO intraparty elections and other hot-button issues.

“The stage is set to get rid of Mukhriz and replace him with Alor Setar UMNO chief Senator Ahmad Bashah Md Hanipah, who goes back a long way with Najib,” according to Imran Imtiaz Shah Yacob, a Mukhriz supporter. “Ahmad Bashah’s long burning desire for the [chief minister’s] post is an open secret.”