Afghan army and NATO-led International Security Assistance Force (ISAF) kept up pressure on insurgents as over 1,400 Haqqani network militants have been captured in Afghanistan so far this year, ISAF spokesman said on Monday.

"Haqqani is a mixture of insurgents and criminals in its network and finances itself out of all types of criminal activities including drugs," ISAF spokesman Brigadier General Carsten Jacobson told a joint press conference with Dominic Medley, NATO's civilian representative's spokesman.

"We chase Haqqani in the field, killing and capturing more than 100 last week alone, and more than 1,400 were captured this year. We also have to break their financial trends," Carsten said. "Haqqani network has link with al-Qaida and receives support of any kind from (some foreign) governments and that support must be stopped."

A Taliban-affiliated militant group, the Haqqani network mostly operates in eastern Afghan provinces and capital Kabul, and were blamed for many high-profile attacks, including a truck bombing on a U.S. military base in Wardak province on Sept 10 and a coordinated attack on ISAF headquarters and U.S. embassy in Kabul on Sept. 13.

Regarding the security transition process from ISAF to Afghan security forces, Medley said the second phase of transition will be announced by Afghan government in coming weeks.

The first phase of transition of security responsibility began in July this year, and the process will be completed by the end of 2014.

NATO civilian representative's spokesman also stated that the alliance would support Afghanistan beyond 2014.

"The NATO commitment is clear. Afghanistan will not be abandoned and the Alliance will stay committed," Medley said.