Colombia has declared a state of emergency in response to widespread riots.

The violence broke out after investors lost millions of dollars in the collapse of pyramid schemes.

Under the state of emergency the Government has special powers to increase prison terms for illegal money collecting and to seize money from businesses involved in such activity.

President Alvaro Uribe says money recovered from the illegal businesses will be repaid to poor investors who lost their savings.

He added, however, that richer investors should have known better and would have to suffer some of the financial blow.

The pyramid style schemes promised extravagant returns and while most investors were poor, senators and police officers were among those who lost out.