Police secure the area near the Berliner Dom prior to the state funeral of former German President Roman Herzog in Berlin, Germany, January 24, 2017. REUTERS/Fabrizio Bensch

GREIFSWALD, Germany (Reuters) - German Chancellor Angela Merkel said on Friday that security would be a major issue in the campaign leading up to a federal election on Sept. 24, in which she is seeking a fourth term.

Concern about security is widespread in Germany after more than a million migrants, mostly from the Middle East and Africa, entered the country over the past two years. That, along with several attacks carried out by migrants, has widened support for the anti-immigrant Alternative for Germany (AfD) party.

“People feel that a lot of things are changing. I think the issue of security will play a key role in the coming months,” Merkel said at a meeting of her conservative Christian Democrats (CDU) in the northeastern city of Greifswald.

She said that was true of social security as well as domestic and external security.

A Forschungsgruppe Wahlen poll published on Friday showed the CDU and its Bavarian sister party - the Christian Social Union (CSU) - would together win 36 percent of the vote if the election were held on Sunday.

The poll put the conservatives’ junior coalition partner, the Social Democrats (SPD), on 24 percent.

Merkel said she was optimistic that her CDU and the CSU would be able to come up with a joint election program. The two parties have frequently been at odds over how to deal with the migrant influx.