South Korea's ex-President Yoon detained again

South Korea's disgraced ex-President Yoon Suk-yeol returned to prison on Thursday as prosecutors investigate accusations of insurrection after he declared martial law last December.

He is being held in a solitary cell at the Seoul Detention Center, where he spent 52 days earlier in the year before his release four months ago on technical grounds.

The Seoul Central District Court said it approved a second warrant because of concerns Yoon could seek to destroy evidence.

What is Yoon accused of?

Yoon triggered months of political turmoil in South Korea after declaring martial law in early December, and then sending armed soldiers to parliament in an attempt to stop lawmakers from voting down his decree.

He has also faced accusations that he authorized drone flights to the North Korean capital, Pyongyang, to help justify his declaration, as well as of falsifying official documents relating to it.

Yoon, 64, has said his decision to declare martial law was necessary to "root out" pro-North Korean and "anti-state" forces.

But the Constitutional Court, which confirmed Yoon's impeachment on April 4, said his acts were a "betrayal of people's trust" and "denial of the principles of democracy."

Life sentence possible

In January, he was detained in a dawn raid after weeks of resisting arrest, becoming the country's first sitting president to be taken into custody, but was released on procedural grounds in March.   

His present detention comes after he on Wednesday attended a warrant hearing that lasted about seven hours during which he rejected all charges.

At the hearing, Yoon's legal team described the detention request by prosecutors as unreasonable and claimed that the ex-leader "no longer holds any authority" after his impeachment.  

Yoon faces criminal charges of insurrection over his martial law decree, which could carry a sentence of life in prison or death.

Although South Korea still has capital punishment on the books, it has had a de facto moratorium on executions since 1998. At the same time, several dozen people are still technically on death row.