East Timor authorities would employ the expertise of an Australian expert to hopefully unearth more clues on the identities of the bones that were accidentally discovered by local construction workers in Dili, the tiny nation's capital.

According to Agence France Presse (AFP), workers unintentional dug open what Timorese officials believed as a mass grave that dates back to the Indonesian invasion of the country, located more than 600 kilometres northwest of Darwin.

The grave, which reportedly carries bone parts by up to 52 persons, was located within the compound where East Timorese Prime Minister Xanana Gusmao holds office.

Initial reports provided by local police officials had indicated that the bodies buried in the site were not of Timorese origin judging from their sizes.

"We look at the heads and they are very big and some bones are very long. In summary I think they are not Timorese," East Timor police chief Calisto Gonzaga told AFP on Wednesday.

He hinted that the rest of the probe will depend on the findings of Australian professor Damien Kingsbury, who had initially presumed that the bones could be that of Chinese residents that were living in the island prior to the Indonesian occupation.

Mr Kingsbury will be picking up on the 11 bodies that Timorese officials have so far completed, Mr Gonzaga.

He stressed that investigators have so far ascertained that 52 bodies were in the grave, which they assumed was first dug up shortly after Indonesian troops descended into East Timor in 1975, sparking a 25-year conflict that claimed the lives of at least 102,000 Timorese, most of them civilians.

Mr Kingsbury already ruled out the possibility that the bones belonged to Indonesians, saying it was unlikely that the invasion army would bury their compatriots in a common pit.

It could be that the bodies were of Portuguese origin, basing on the sizes of the bodies that were reported by Timorese officials, the Deakin University expert said, but the likelihood that they were Chinese offers the more logical conclusion.

"The Chinese were still in Timor when the Indonesians invaded in 1975 and they were one of the primary targets of the Indonesian military at that time," Mr Kingsbury told AFP.

East Timor was once ruled by Portugal and gained its independence in 1975 but its liberty proved short-lived when Indonesia sent troops to the country and annexed it in the following year.

The country regained its independence in 2002 but not before suffering hardships under Indonesian rule, which was highlighted by the Dili Massacre in 1991 that killed 250 people.

Some clips of the attacks were filmed by Western journalists and first shown in January 1992 by UK-based ITV, sparking outrage around the world that had accelerated East Timor's independence.