Protests against asylum-seekers in the German city of Cologne turned violent on Saturday as protesters threw beer bottles and firecrackers at the police, who in turn used water cannons to disperse them. Four people were injured in the clash.

The protesters hurled beer bottles at the law enforcers, shouting: "Where were you on New Year's Eve?" The police used batons, tear-gas and water cannon to disperse the protesters. At least three police personnel and one journalist were injured in the clash, AFP reported.

The German Police reportedly detained several demonstrators. A total of 2,000 police personnel were deployed at the protest site.

The demonstration march was against the refugees as several of them are suspected to be behind the mass sexual assault on women and robberies at Cologne station on 31 December. The protest was also against the Cologne police, who faced criticisim for their handling of the assaults.

The police have received as many as 379 criminal complaints as of Saturday. Nearly half of the complaints are reportedly about groping, assaults and thefts. Two rapes have also be reported.

"Those in focus of criminal police investigations are mostly people from North African countries. The majority of them are asylum-seekers and people who are in Germany illegally," The Telegraph cited a police statement as saying.

More than 1,700 people had joined the protest oganised by far-right anti-Islam PEGIDA (Patriotic Europeans Against the Islamisation of the Occident) in the Cologne railway station area.

Several of the demonstrators shouted slogans such as, "This is the march of the national resistance", while a banner read: "Rapefugees not welcome", according to Reuters.

A counter-protest was also organised by Left-wing activists. It was attended by at least 1,300 supporters who chanted "Nazis raus!" (Nazis out!). A few Iraqi and Syrian refugees also joined them.

"We are there to tell them to shut up. It is unacceptable for PEGIDA to exploit this horrible sexual violence perpetrated here on New Year's day and to spread their racist nonsense," AFP quoted Leftist protester Emily Michels as saying.

Protest against Merkel

Right-wing protesters also held demonstration against German Chancellor Angela Merkel for her soft stand on allowing refugees of war-torn countries in Germany. "Merkel has become a danger to our country. Merkel must go," one of the speakers had said earlier, according to AFP.

In 2015, Germany gave refuge to around 1.1 million migrants, including those from Iraq and Syria. 

Hours before the protest in Cologne, Merkel had declared that her Christian Democrats (CDU) party had decided to make amendments to the law allowing ease in the deportation of migrants who commit crimes.

"The right to asylum can be lost if someone is convicted, on probation or jailed. Serial offenders who repeatedly rob or repeatedly affront women must feel the full force of the law," Reuters quoted Merkel as telling journalists in Mainz.

The law in force at present allows Germany to deport asylum-seekers only if they are sentenced to at least three years in prison and if their lives are not at risk in their own country.