A Jordanian judge Sunday ordered the release of the teachers union's 13 elected council members who were arrested a month ago for alleged graft, a judicial source said.

Authorities closed the union and arrested its leaders on July 25 after it had led a campaign for higher pay in the indebted kingdom whose economy is reeling from the coronavirus pandemic.

The government also imposed a gag order against publication of details of the prosecutor's investigation into the case.

Teachers' Association lawyer Bassam Freihat confirmed the release of the 13, including acting head of the union Nasser Nawasreh.

The lawyer told AFP they had completed a one-month detention period without the bail allowed by the judicial system.

"The court also decided to release a number of teachers who had been arrested during demonstrations" before and after the arrest of their leaders, Freihat said.

Neither the judicial source nor the lawyer were able to give further details or say whether the 13 would face further legal action.

But the union remained closed even as Jordan's schools were due to reopen on September 1 and teachers returned to state-run schools on Sunday to prepare for the new term.

In July state prosecutor Hassan Abdallat ordered a two-year closure of the union's headquarters, its branches and offices nationwide and the arrest of the 13-member union council.

They were accused of unspecified "financial violations" and questioned on criminal and corruption charges, state media reported at the time.

On Tuesday, Human Rights Watch said the gag order banning the media from covering the case was the "latest in a series of restrictions on press freedoms".

At least two journalists were arrested for covering union protests and two others beaten, the watchdog said.

"Jordan's shrinking space for journalists to operate reflects the country's slide into repression," said HRW's deputy Middle East director Michael Page.