Liverpool were handed a scare when Salah, the Premier League's joint top scorer this season with Manchester City's Erling Haaland, limped off just before halftime in Egypt's 2-2 draw with Ghana at the Africa Cup of Nations on Thursday.
"We don't know anything about it," Klopp told reporters on Friday. "I spoke with him last night and how it was. They are doing further assessments now and then we will know more.
"At that moment he was shocked and couldn't see why he was hit by something so intense. You have these hamstring injuries in a different way. He felt it and we know how rarely Mo goes off, or needs to go off, so it is definitely something, but I don't have any more information right now."
Salah is rarely injured and has missed just 10 league games in six-plus seasons.
Klopp said he was uncertain whether Liverpool's medical staff would travel to the Ivory Coast to assess the extent of Salah's injury.
"We will see. It depends on the diagnostics," he said. "We will have ultrasound and MRI and then we will know what it is and we will see and make plans, but it's too early (at the moment)."
Liverpool, who play at Bournemouth on Sunday, top the Premier League on 45 points after 20 games, two points clear of Manchester City. Aston Villa also have 43 points but have played one more game than the two sides above them.
Liverpool will likely be without Trent Alexander-Arnold again on Sunday, Klopp said, after the defender injured his knee in their FA Cup third-round win over Arsenal on January 7th.
"Obviously he can walk, on the catwalk," Klopp said, when asked about Alexander-Arnold being spotted at a fashion show this week in Milan.
"The injuries are all positive, but not ready. (Alexander-Arnold, Andy Robertson and Dominik Szoboszlai) are all going in the right direction but we will see when they can join first-team training. I don't expect them for Bournemouth.
"I hope that nobody else will be out," the manager added. "After Bournemouth and maybe for Fulham (League Cup semi-final on Wednesday). Trent is close, Robertson close and Dom close. So all going in the right direction but for the weekend's game, no."
