Ebola burial teams in Sierra Leone are extorting money from families of the bereaved to give the dead safe burials, a senior health official said, leading to an increase in illegal funerals.

The introduction of anti-Ebola measures requiring bodies to be buried according to safety protocols was considered a key sign of progress in the fight against the disease last year.

Formerly, families were secretly burying bodies in unmarked graves, using traditional practices which can spread the virus via the highly infectious fluids of the deceased.

Palo Conteh, head of the National Ebola Response Centre, told reporters on Wednesday that some teams are now soliciting bribes of around 1 million Sierra Leonean Leone ($247) from the families of the bereaved for the service.

Conteh said allegations that burial teams from Connaught Hospital had demanded bribes were being investigated. He did not give details of where the new illegal burials were happening.

The worst-known Ebola epidemic in history has killed more than 11,200 people, mostly in Guinea, Liberia and Sierra Leone.

Case numbers have fallen sharply since their peak last year, the region reported 30 new cases in the week to July 12, mostly in or around the capital cities of the three countries.

In a major setback, formerly Ebola-free Liberia declared a new case on June 30 and five more cases since.

Conteh added that Sierra Leone would re-open the formerly shut 34 Military Hospital to Ebola patients in order to deal with the rise in new cases in the capital.

In addition, Sierra Leone's Parliament has adopted recommendations by its Public Accounts Committee to suspend three government officials for violating procurement rules in the management of Ebola funds. The country's auditor said in February that the government had failed to fully account for nearly a third of the $20 million earmarked for fighting the disease.