MAPUTO (Reuters) - Mozambique's ruling Frelimo party was headed for a resounding victory in national polls on Sunday that would allow it to change the constitution at will and hand President Armando Guebuza a second term in office.

Estimates released on Sunday gave Guebuza 75 percent of the presidential vote, with Frelimo set for a two-thirds majority in parliamentary elections that took place on Wednesday.

Afonso Dhlakama, candidate for the opposition Renamo party, was seen taking 15 percent of the vote in the presidential contest, with Davis Simango, head of the new Movement for Democratic Change (MDM) party, seen on 10 percent.

The estimates were compiled by the Mozambique Political Process Bulletin of the Association of European Parliamentarians of Africa (AWEPA) and the Centre for Public Integrity (CIP), a Mozambican non-governmental organisation.

According to figures based on 72 percent of the vote counted, Frelimo had secured 192 seats, Renamo 48 and the MDM 8 in the 250-member parliament.

"There are fears that the party will amend the constitution to allow Guebuza to run for a third term and this is definitely not good for democrary. There should be space to balance opinion," political analyst Moises Mabunda told Reuters.

No estimates have yet been released from provincial polls also held on Wednesday.

Guebuza's Frelimo party has ruled Mozambique since it led the country to independence from Portugal in 1975.