The trapped Chilean miners have been sent down hot packaged food.

Meals, consisting of meatballs, chicken and rice, have been sent through a tube to the 33 miners, stuck 700 metres below the surface at the San Jose mine in Copiapo.

Up to now, the miners have only been fed glucose tablets and high-protein milk.

On Wednesday, a team from the US space agency NASA arrived at the mine to offer advice on how to help the miners cope with health problems in cramped conditions.

A nutritionist from the NASA team put together the hot food menu.

Rescue attempts to extract the men from the mine are expected to take three to four months.

Engineers have already drilled through 20 metres of rock after beginning work on Monday.

A "Plan B" separate shaft is being drilled from another part of the mine.