Bavarian Minister President Horst Seehofer lashed out against German Chancellor Angela Merkel’s “open-door” refugee policy and the threat of Islamic extremism on Saturday when he refuted Merkel’s “we can do this” approach in defending her actions.

Three of the four attacks that took place in Germany since July 18 occurred in Bavaria. As the leader of Bavaria, a German state that suffered multiple attacks led by asylum-seekers since Germany welcomed more than 1 million refugees in 2015, Seehofer indicated that he would not sit idly by as the attacks increased.

“‘We can do this’ – I cannot, with the best will, adopt this phrase as my own,” Seehofer said after a political party meeting this week, according to Reuters. “The problem is too big for that and the attempts at a solution thus far too unsatisfactory…Restrictions on immigration are a condition for security in this country.”

Fifteen people have been killed in the five attacks that occurred in Germany since July 18. Of those five attacks, at least two of them have been claimed by the Islamic State.

Merkel received criticism and backlash after she defended her refugee policies during a press conference on Thursday. Claiming that Germany “will manage” the integration of the 1 million refugees and the growing threat of Islamic extremism, Merkel said she would do “everything humanly possible” to preserve Germany and its citizens. Merkel’s plan promotes a nine-point strategy of response, including an attempt at a preemptive warning system that would monitor for the radicalization of refugees.

“A ban on the full body veil – that is the niqab and the burka – is overdue,” Jens Spahn, a deputy finance minister and senior member of Merkel’s party, told daily Die Welt. Spahn added that it would be nearly impossible to successfully integrate all of the refugees into Germany.

“My impression is that we all underestimated a year ago what would come upon us with this big refugee and migration movement,” Spahn added.