WASHINGTON (CBSMiami) – Attorney General Jeff Sessions has vowed to “leave no stone unturned” to find missing text messages tied to the Russia investigation.

Republicans say the texts may show bias by the FBI’s Peter Strzok and Lisa Page, who once worked for Special Counsel Robert Mueller.

Tuesday morning, President Donald Trump commented on the missing texts on Twitter.

“We need to get to the bottom of it and find out exactly what happened,” said Rep. Jim Jordan, D-OH.

Strzok and Page exchanged thousands of texts, frequently discussing the Clinton investigation as well as their dislike of Trump.

In one from February 2016, Page texted Strzok that then-candidate Trump “simply can not be president.” In another, Strzok called Trump an “idiot” and “awful.”

Strzok and Page also discussed former FBI Director James Comey’s statement exonerating Hillary Clinton’s use of a private email server.

An early draft noted Secretary Clinton emailed with President Barack Obama from her private server. But the sentence was later edited to replace the president with “a senior government official.” Strzok and Page also discussed using non-work phones to talk about Clinton so it “can’t be traced.”

During the Department of Justice’s investigation into Strzok, it found texts were missing between December 14th, 2016 and May 17, 2017. Those dates span the presidential transition and the day Robert Mueller was appointed.

The FBI has blamed software and technical issues. It said some employees with Samsung 5 mobile devices did not capture texts during that time.

Last month on Face the Nation, Republican Senator James Lankford said Strzok’s comments called into question his role in Mueller’s investigation.

“It’s clear this individual within the Mueller team that was also on the Clinton e-mail investigation team on the FBI, in their leadership, had a strong bias against now President Trump,” said Lankford.

On Monday, FBI Director Chris Wray visited the White House to discuss the five months of missing texts which appear to impact many more agents in addition to Strzok and Page.