WRAPUP 5-Pakistan vows to hunt Mumbai attack plotters - Rice

* Rice says Pakistan understands need to root out militancy

* President Zardari vows strong action

* India says attackers controlled from Pakistan

* Tight security in Islamabad for Rice visit

By Sue Pleming and Robert Birsel

ISLAMABAD, Dec. 4 (Reuters) - U.S. Secretary of State Condoleezza Rice said in Islamabad on Thursday that Pakistan gave assurances that it would root out terrorism and round up anyone connected to last week's attack in the Indian city of Mumbai.

Rice said the fight against terrorism was a "global struggle" in a news conference at the end of a brief visit to Pakistan aimed at curbing tensions between the nuclear-armed South Asian neighbours.

In a delicate balancing act, Rice met Indian leaders a day earlier in New Delhi, where she called for restraint. Rice said she had reasonable and responsible discussions in both capitals.

The sophistication of the attacks that killed 171 people, including six Americans, in India's commercial capital was alarming and all sides had to work together to stop this kind of attack happening again, she said.