A number of trenches, part of an archaeological project collapsed in Paravoor near here but a major tragedy was averted as researchers and workers were not present there at the time of the incident.
The wall between trench number 16 and 17 went down with huge sound, just two hours after the works stopped, witnesses said.
"The work at the site starts from 6.30 in the morning and ends up by 2.30 in the afternoon. So, luckily there was nobody at the site during the time of trench collapse," a worker said.
P J Cherian, Pattanam excavation director said there was fine sand at the bottom layer which might have moved when there is water-logging. There was nobody near the trenches when the collapse happened, he said.
In a breakthrough excavation, researchers had unearthed 18 wooden pegs with pointed edges and two massive urn-like terracotta structures from the site last week.
The pegs were found at the trench number 18 and the urns were spotted in the trench number 17, researchers said adding that the collapse of the wall near the trench-17 had made the marking of the layers difficult.
Historians and archaeologists are in an effort to find out whether Pattanam is the ancient port city 'Muziris' which is believed to have existed on the banks of river Periyar
centuries back.
Kerala Council for Historical Research (KCHR)has been conducting excavations at Pattanam since 2007 with the approval of Archaeological Survey of India (ASI).