Rapid turnover in the top military leadership of the Philippines is sparking speculation of unrest in the armed forces. But defense officials say there is no cause for alarm.

The shakeup started late last week. President Ferdinand Marcos Jr. cut short the term of the chief of staff on Saturday, replacing him with a retired general.

Acting Secretary of Defense Jose Faustino also handed in his resignation. He said he was quitting because he didn't know about the appointment of the new chief of staff. Marcos accepted the resignation and has appointed Carlito Galvez Jr. as the new defense chief.

Despite the turmoil, senior defense officials stressed everything was calm. Philippine Defense Department Undersecretary Angelito De Leon said, "The one defense team should remain united and should pursue and focus on its mandate."

The role of the Philippine military has come into focus as China steps up its activities in the South China Sea. The new leaders are tasked with protecting the country's maritime boundaries amid increased regional tensions.