CARACAS, Venezuela (AFP) — Venezuela’s electoral authority on Wednesday rejected as “irresponsible” a claim that the official turnout figure for a weekend vote that elected a controversial new assembly was false.

Earlier, Smartmatic, a British firm that supplied the technology for the ballot, said the turnout figure of more than eight million was “manipulated” and exceeded the real number by “at least one million votes.”

“This is an irresponsible contention based on estimates with no grounding in the data” that was “exclusively” handled by the National Electoral Council, said its president, Tibisay Lucena.

“This is an unprecedented opinion from a firm whose only role in the electoral process is to provide certain services and technical support that had no bearing on the results,” she told reporters.

While the authority had claimed a turnout of 8.1 million to elect the body, the Constituent Assembly, the opposition said the figure was closer to 3.5 million.

Significantly, the opposition had held an unofficial referendum on July 16 in which it said 7.6 million Venezuelans voted against the new assembly — just under the level of support the government claimed to have received last Sunday.

Because of an opposition boycott, it was a foregone conclusion that followers and allies of President Nicolas Maduro’s Socialist Party would fill all the Constituent Assembly posts. So the turnout figure was the key gauge of public support.

Smartmatic said the official turnout figure had been “tampered with.”

Smartmatic chief executive Antonio Mugica said: “Based on the robustness of our system, we know, without any doubt, that the turnout of the recent election for a National Constituent Assembly was manipulated.”

Maduro was to swear in the Constituent Assembly later Wednesday. It is due to start work Thursday, in the legislative palace that up to now had been the seat of the opposition-controlled congress, the National Assembly.

The Constituent Assembly is tasked with rewriting the constitution, and has the power to dissolve the legislature.

Its election was opposed by street protests and widely criticized internationally as damaging or destroying Venezuelan democracy.