SEOUL, July 10 – On Thursday, former South Korean President Yoon Suk Yeol was taken back into custody after the court sanctioned a request from prosecutors to detain him for his attempt to enforce martial law the previous year.

The decision from the Seoul Central District Court strengthens the special counsel’s investigation into claims that Yoon’s actions in December were attempts to obstruct justice and abuse his power.

The court said in a statement it granted the request because of concerns Yoon could seek to destroy evidence.

The conservative leader is already facing legal charges of insurrection due to his martial law declaration, which could potentially lead to a life imprisonment sentence or even the death penalty.

The former president returned to confinement in the Seoul Detention Center about 20 km (12 miles) south of the capital after the decision. He spent 52 days in jail earlier in the year but was released four months ago on technical grounds.

The Constitutional Court ousted him as president in April, upholding parliament’s impeachment for the martial law bid, which shocked South Koreans and triggered months of political turmoil.

The special prosecution team launched its investigation after new leader Lee Jae Myung was elected in June, and it has been looking into additional charges against Yoon.

The special counsel team is now expected to speed up its probe into allegations, including whether Yoon hurt South Korea‘s interests by intentionally inflaming tensions with North Korea.

Yoon attended the court hearing on Wednesday on the detention warrant, wearing a dark navy suit and a red tie, but did not answer questions from reporters.

His lawyers have denied the allegations against him and called the detention request an unreasonable move in a hasty investigation.

More than 1,000 supporters rallied near the court on Wednesday, local media reported, waving flags and signs and chanting Yoon’s name in heat of 35 degrees Celsius (95 degrees Fahrenheit).

In their warrant request, prosecutors said Yoon poses a flight risk, local media reported.