Angela Merkel's ruling CDU party has been beaten into third place by an anti-immigrant and anti-Islam party in elections in a north-eastern German state, partial results have shown, according to BBC News.

The Alternative fuer Deutschland (AfD) party took about 21% of the vote behind the centre-left SPD's 30%.

The German chancellor's CDU was backed by only about 19% of those who voted, according to the partial results.

The vote was seen as a key test before German parliamentary elections in 2017.

Before the vote in Mecklenburg-West Pomerania, in the former East Germany, all of Germany's other parties ruled out forming a governing coalition with the AfD.

However, the party's strong showing could weaken Merkel ahead of the national elections next year, BBC News said.