BP stock plummets after chairman Albert Manifold is suddenly fired.

British energy giant’s stock price blood pressure Shares fell sharply on Tuesday after the company’s board announced it had fired Chairman Albert Manifold in a surprise move.

The company said in a statement that the decision to immediately fire Mr. Manifold followed “serious concerns” about governance standards, oversight and conduct, without providing further details.

“Albert brings a welcome focus and pace to BP’s transformation,” said Amanda Brann, senior independent director at BP. “However, the board was surprised, disappointed and took decisive action to learn of issues of governance oversight and conduct that it considers unacceptable.”

On the news, London-listed BP shares fell as much as 9% before offsetting losses. The stock was last down about 4%.

BP has announced the appointment of Ian Tyler as interim chair with immediate effect, noting that the process for succession to a permanent chair will begin.

“The board and management team have deep conviction in the strategic direction we have set, and the company is moving at a rapid pace to realize it,” Tyler said.

“BP has a track record of strong fundamental operating results and a focus on financial discipline in the pursuit of increasing shareholder value and profits,” he added.

CNBC has contacted the UK’s Serious Fraud Office and is awaiting a response. The Metropolitan Police Department declined to comment.

Manifold, who has only been chairman since October, received lower-than-usual support at BP’s annual general meeting last month following an investor revolt.

A majority of 81.8% of shareholders voted in favor of electing the former president of Irish building materials giant CRH as BP chairman. Electing board members requires 50% of the vote and typically receives close to 100% support.

Some activist investors had said even a 5% vote for Manifold would mean a harsh rebuke, especially after the historic 24% vote for outgoing chairman Helge Lund last year.

Manifold’s firing comes as the energy giant pivots away from renewable energy and back to its core oil and gas business, with former Woodside Energy president Meg O’Neill taking over the reins as CEO.

O’Neill took over as CEO on April 1, after less than two years in the role, replacing Murray Auchincloss.

Maurizio Carulli, Global Energy Analyst at Quilter Cheviot, said: “The announcement of Albert Manifold’s departure is certainly a surprise. That said, BP has seen a significant number of senior leaders suddenly leave the company over the past 20 years, including former CEO Lord Browne, Tony Hayward, Bernard Rooney and Murray Auchincloss, all of whom had very different individual circumstances leading to their departure.”

“While this news is clearly negative in the short term, it is important to remember that BP has undergone significant operational improvements and strategic refocus over the past year, and this is the result of the successful efforts of not just one person, but the entire organization and its management team,” he added.

Lindsey Stewart, Morningstar’s director of institutional content, said Manifold’s ouster is evidence that BP has “the most volatile boardroom” of any major oil company.

Referring to BP’s controversial decision to block a proposal submitted by Dutch activist group Follow This at a shareholder meeting, Stewart said: “The company’s decision to exclude a shareholder proposal that appeared to meet all the conditions for a shareholder vote led to an unnecessarily broad investor backlash and once again raised questions about the company’s governance and oversight.”

“BP should benefit from a strategic reset given its share price recovery since the start of this year,” Stewart continued. “Instead, the company is on its third CEO and now its third chairman in less than three years. It’s clear that understanding the company’s corporate governance and strategy is a priority for the interim chairman and his eventual successor.”

Climate change group ACCR called on BP’s board to provide a “full and transparent explanation” of what exactly led to Manifold’s dismissal, while Forou This said the new chair must bring “genuine expertise” on governance, climate risk and transition risk.