Popular support for Chancellor Angela Merkel has plunged according to a poll conducted after attacks in Germany, with almost two-thirds of Germans unhappy with her refugee policy. The survey for public broadcaster ARD showed support for Merkel down 12 points from her July rating to 47 percent. This marked her second-lowest score since she was re-elected in 2013. In April last year, before the migrant crisis erupted she enjoyed backing of 75 percent. Merkel's open-door refugee policy has come under attack from critics after five attacks in Germany since July 18 have left 15 people dead, including four assailants, and dozens injured. Two of the attackers had links to Islamist militancy, officials say. Support for one of Merkel's fiercest critics, Bavarian Premier Horst Seehofer, who has called for restrictions on immigration to increase security, jumped 11 points to 44 percent. Over a million migrants have entered Germany in the past year, many fleeing war in Afghanistan, Syria and Iraq. Merkel repeated her claim that Germany could manage to successfully integrate the influx of refugees last week and vowed not to change her refugee policy. In a poll of 1,003 people conducted Aug. 1-2, just 34 percent of people said they were satisfied or very satisfied with Merkel's refugee policy. This was the lowest level since the question was first asked last October. Some 65 percent were dissatisfied with the policy. The next test of support for Merkel will be state elections in Mecklenburg-Vorpommern on Sept. 4, where her Christian Democrats (CDU) are expected to face a strong challenge from the anti-immigrant Alternative for Germany (AfD) party. A separate poll this week showed that most Germans do not blame the government's liberal refugee policy for the two Islamist attacks last month.