A federal judge has extended special counsel Robert Mueller's federal grand jury six months.

The Washington-based grand jury was seated for an 18-month term that began in July 2017 and was set to expire in the coming days.

Chief Jude Beryl Howell of the D.C. District Court oversees the Mueller grand jury and granted the extension, CNN’s Katelyn Polantz reported.

Under federal rules, the court is able to extend a grand jury's term for another six months if it is "in the public interest."

Howell, who was appointed in 2010 by former President Barack Obama, does not sit in on the grand jury sessions. The sessions by the 23-person group are secret, except when it approves criminal indictments that are public when unsealed.

There has been widespread speculation that the special counsel’s investigation into Russian election interference and possible ties to the Trump campaign was wrapping up. But the grand jury extension and the delayed sentencing of three of President Trump’s former top aides suggests there is more work to do.