King has not played for Spurs since their 1-1 draw against Chelsea on December 22 as he has struggled to return to full fitness because of his chronic knee troubles.
It was hoped that the 31-year-old, who played just nine games last season, would return at centre-back for Wednesday's huge Barclays Premier League game against the Toffees, but King pulled up in training on Friday holding his hamstring, however, and manager Harry Redknapp fears the defender has suffered a tear.
The news comes at the worst possible time for Redknapp, who only has Younes Kaboul, wantaway defender Sebastien Bassong and Michael Dawson, who has just returned from a four-month Achilles injury lay-off, available at the back.
"Ledley did his hamstring on Friday," Redknapp said.
"He had a little jog and tore his hamstring, we think. He has gone for a scan.
"We don't have the results yet but he only went for a little easy jog and his hamstring went."
Should King be ruled out for a long time, Redknapp may be forced to step up his bid to bring in a defender, with Blackburn's Christopher Samba thought to be high up on his shortlist.
"I have not got many options," Redknapp said.
"I only have Dawson, Bassong and Kaboul. No-one else."
Source: PA
Source: PA