Germany’s opposition leader has vowed to bar people from entering the country without proper papers and to step up deportations if he is elected as chancellor next month.

And with just one month to go until Germany's federal elections, the incident has further enflamed an already heated immigration debate in the country. Friedrich Merz, leader of the center-right opposition Christian Democrats and favorite to become Germany's next chancellor,

The motives for the stabbing are still unclear, with police asking for witnesses to submit evidence. A stabbing in the southern German city of Aschaffenburg has left two people dead on Wednesday, local police said.

Germany's main opposition leader vowed on Thursday to impose immediate border controls if he becomes chancellor, as expected, after elections next month, a day after an Afghan asylum seeker was arrested for a deadly knife attack targeting children.

The violent attack left two dead, including a 2 year-old boy, and three injured in the Bavarian city. The suspect is a former Afghan asylum seeker with a history of psychiatric problems and violence who said over a month ago that he would leave Germany voluntarily.

A knife attack in Aschaffenburg, Germany, left two dead and two injured. An Afghan suspect was arrested as authorities investigate the motive.- Watch Video on English Oneindia

A two-year-old boy and a 41-year-old man were killed on Wednesday in a knife attack in Germany's Aschaffenburg. A 28-year-old man from Afghanistan has been arrested by the police.

A 28-year-old man from Afghanistan was arrested following a knife attack on Wednesday in a park in the German city of Aschaffenburg in which two people were killed, including a toddler, police and the state health minister said.

The chairman of the party and fraction of the Christian Democratic Union (CDU), Friedrich Merz, gives a press conference in the German parliament in Berlin, in reaction to the knife attack on January 22 in Aschaffenburg.

A knife attack that killed two people in the Bavarian city of Aschaffenburg has left a local community in grief, with the city's mayor warning of a "spiral of violence and hatred." An Afghan suspect is in custody.

Germany is working intensively to deport more criminals to Afghanistan, said Interior Minister Nancy Faeser in Berlin on Thursday, a day after an Afghan asylum seeker was arrested for a deadly knife attack.