Gambia's largest opposition party has named its candidate to challenge longtime President Yahya Jammeh in December's presidential elections.

United Democratic Party candidate Adama Barrow accepted the nomination Thursday, saying the people of this West African country are yearning for change.

Barrow's nomination comes as party leader Ousainou Darboe and other party supporters, including 14 executive members, are serving three-year prison terms. They were arrested during peaceful demonstrations in April and May that called for electoral and political reforms.

Three opposition party members died in detention after the protests.

Rights groups accuse Jammeh of human rights abuses, including a clampdown on political opponents.

The president is one of Africa's longest-serving leaders. He has been in power since 1994.