US officials are discussing an option that would keep a small residual military force in north-east Syria to secure oil fields and continue the fight against Daesh.

Defence Secretary Mark Esper said he had not made a final decision on that option and has not yet presented it to President Donald Trump.

READ MORE: Kurds evacuate key Syrian border town as US redeploy to Iraq

Speaking at a press conference in Kabul, Afghanistan, Esper said some American forces that are in north-east Syria have not yet started to withdraw.

He said they are working with Syrian Kurdish fighters to secure the oil fields in the region so they do not fall under control of Daesh.

Esper said the troops around Kobani are withdrawing first and that troops in the north-east are still in the towns near the oil.

He also said the US is maintaining combat air patrol over US forces as the withdrawal goes on.

MEANWHILE, prosecutors in Slovakia have indicted four suspects for the killing of an investigative reporter and his fiancee in a case that brought down the country’s government.

The National: Light tributes placed during a silent protest in memory of murdered journalist Jan Kuciak and his girlfriend Martina Kusnirova, seen in photo, in Bratislava, SlovakiaLight tributes placed during a silent protest in memory of murdered journalist Jan Kuciak and his girlfriend Martina Kusnirova, seen in photo, in Bratislava, Slovakia

The four include the alleged mastermind and a businessman who was long suspected of involvement in the crime.

The prosecutors previously identified him as Marian K, omitting his full surname as is standard in Slovakia.

Reporter Jan Kuciak and his fiancee Martina Kusnirova were shot to death in their home on February 21 last year.

Slovak authorities believe it was a contract killing linked to Kuciak’s work investigating possible government corruption.

ELSEWHERE, protests and violence in Chile, prompted by a subway fare rise, has continued with violent demonstrations.

Officials in the Santiago region said three people died in fires at two looted supermarkets early on Sunday. The stores are among 60 Walmart-owned outlets that have been vandalised, and the company said many stores did not open during the day.

The National: Police detain a demonstrator in Santiago, ChilePolice detain a demonstrator in Santiago, Chile

Five more people were later found dead in the basement of a burned warehouse, authorities said.

At least two airlines cancelled or rescheduled flights into the capital.

FINALLY, Zimbabwean authorities say at least 55 elephants have starved to death in the past two months in the country’s biggest national park amid a serious drought.

National Parks and Wildlife Management Authority spokesman Tinashe Farawo called the situation dire, with other animals such as lions affected.

He said animals are straying from wildlife parks to seek food and water in nearby communities where they destroy crops and sometimes kill people.

Farawo said the park can handle 15,000 elephants but currently has about 53,000.