SANTIAGO - Chile's constitutional convention rejected on Thursday night a set of proposals focused on expanding environmental protections, especially around the major mining sector, a blow to reformers which will push the articles back to committees to be reworked.

"Regretfully, our commission's [full proposal] was rejected," Camila Zarate, an environmental commission coordinator, told reporters after the vote. "We regret that [the assembly] gave its back to citizens, communities, the population and territories that have been mobilizing for years to make these great changes in this constitutional text."

Juan Jose Martin, the other commission coordinator, said he regretted that the entire set of proposals was voted down because it gave the commission no feedback about which proposals constituents objected to.

Martin Arrau, a constituent and civil engineer who previously led a water reform campaign, said he voted against the proposals because he thought some would hinder growth and others were outside the constitutional jurisdiction.

"When it comes to the hydrological sources, basins, they have to be regulated by law and public policy, not in the constitution," Arrau told Reuters after the vote. "If not, how are we going to have judicial and public frameworks that adapt to the variability of water sources?"

The debate started at 12 p.m. local time (16:00 GMT) and for more than six hours constituents gave impassioned speeches about environmental rights, the damage caused by extractive activities like mining and forestry, and the effects of Chile's historic drought throughout the country.

Constituents were expected to vote on 52 articles including protecting water sources, glaciers and wetlands well into the night. But when voting started, constituents rejected the entire proposal, preventing voting on individual articles and sending it back to the commission for changes.

The proposal and articles need a super-majority of 103 votes to be approved; Thursday's set of proposals fell short with 98 votes in favor, 46 against and 8 abstaining.

Chileans overwhelmingly voted to draft a new constitution in 2020 a year after protests against inequality rocked the Andean country. But political infighting and controversial suggestions have led to a drop in support for the process. Read full story

The assembly has until mid-May to approve articles for the draft constitution and until July to have the draft fully completed. Chileans will vote to approve or reject the new constitution on September 4.

If voters reject it, Chile will stick with its current market-oriented constitution, which dates back to the military dictatorship of Augusto Pinochet over three decades ago.