Migrants have tried to jump over the metal barrier to gain entry into the US [Source: BBC]

A seven-year-old girl who US officials say tried to cross the Mexico-US border illegally with her family has died hours after being taken into custody.

The Guatemalan girl, who authorities there have named as Jackeline Caal, died of dehydration and shock, the Washington Post reports.

AP news agency quotes border officials as saying she had not had food or water for several days.

Thousands of migrants have travelled from Central America to the US border.

The migrants say they are fleeing persecution, poverty and violence in their home countries of Guatemala, Honduras and El Salvador.