An archaeological dig searching for the lost grave of Richard III has exceeded expectations during its first week, organisers have said.

Experts from the University of Leicester have so far excavated two 98ft-long (30m) trenches at a car park in the city centre thought to cover the site of a Franciscan friar where the former king is believed to have been buried in 1485.

Working alongside members of the Richard III Society, archaeologists have unearthed medieval window tracery, fragments of glazed floor tiles and a section of wall which may have belonged to the Greyfriars church.

Work at the car park, which is owned by Leicester City Council, began on 24 August with archaeologists using ground-penetrating radar equipment to mark out the trenches.

richard iii grave

Markers are laid out for excavation in Leicester, as two reenactment knights look on

Richard Buckley, co-director of the university's Archaeological Services, said: "It has gone about as well as we could hope for. We aim to dig a contingency trench over the weekend to see if these walls are the church. If this is the case, we can point to the area where Richard III might have been buried.

"The search for Richard goes on. It is still a long shot but the archaeological work we have done so far is revealing more about the archaeology of the Greyfriars area than we ever knew before.

"In that respect, whatever the outcome, whether we find Richard or not, this work is an advance in terms of helping us to tell the story of the city of Leicester."

The dig is being filmed for a Channel 4 documentary to be aired later this year.