Kabul, Afghanistan (CNN) -- Many Afghans were denied the right to vote in parliamentary elections because the country is too dangerous and because of logistical failures, an independent election watchdog said Monday.
But the relatively high level of voter participation and security arrangements for voting on Saturday were positive signs, the Free and Fair Election Foundation of Afghanistan said.
There have already been arrests for vote fraud in the wake of the voting, police in Afghanistan said Monday.
Some 45 people were detained on suspicion of vote fraud in Logar province, police chief Mustafa Mohsini said Monday.
But 39 were released without charge, said Den Mohammad Darwish, a spokesman for the province's governor.
Discrepancies between the number of voters in the parliamentary election and last year's presidential election had already raised questions about Saturday's results.
Saturday night, the Independent Election Commission (IEC) announced it recorded a 40 percent turnout, with 3.6 million votes cast out of a total of 9.2 million eligible voters.
But in the widely criticized presidential elections of August 2009, the IEC reported 11.4 million eligible voters.
And the commission's website reports a total of 16.7 million voters have been registered in Afghanistan since 2003.
Despite praise from U.N. Secretary-General Ban Ki Moon, Gen. David Petraeus, the top U.S. military commander in Afghanistan, and Afghan President Hamid Karzai regarding Saturday's balloting, the statistics suggest a dismal turnout, with nearly a million fewer votes cast than in the national election a year ago.
The IEC reported nearly 4.6 million valid ballots cast last year.
Asked about the discrepancies, an IEC official said the registered voter population was reduced after the commission was forced to close nearly 20 percent of the country's polling centers on Saturday due to Taliban violence.
"Polling centers were closed because of security reasons," said Qani, an official at the foreign relations department of the IEC who, per Afghan tradition, uses only one name.
"The population of those areas were deducted from the total population of registered voters which was 11.4 million."
Some election observers, however, are calling for clarity.
"The different numbers they are presenting are not consistent," said Nader Naderi, the chairman of Free and Fair Election Foundation of Afghanistan, the Kabul-based election watchdog organization.
Afghanistan's electoral process suffered a huge blow to its credibility after investigators found evidence of widespread fraud in the 2009 presidential election.
The United Nations eventually disqualified more than 1 million fraudulent votes.
"We believe and hope that they learned a lesson that massive fraud will be detected and is unacceptable," Staffan de Mistura, the U.N. special representative for Afghanistan, told CNN.
At the polls on Saturday, many voters and candidates expressed doubt and skepticism about the election, which came with a price tag of approximately $150 million.
"I saw fraud many places," said Jamil Karzai, a parliament member who was running for re-election.
"It is not a real election," said Abdul Qader Zazai Watandost, who at the age of 30 was making his second attempt at being elected to parliament.
He accused the IEC of actively supporting candidates at the polls.
"There were large swaths of the population who were unable to participate, whether because they didn't want to or because they were prevented by violence or discouraged by fraud," said Candace Rondeaux, senior analyst with the International Crisis Group.
Despite the deployment of hundreds of thousands of police and soldiers across the country on Saturday, Afghan officials said Taliban-related violence claimed the lives of at least 12 civilians along with at least three Afghan police officers and an Afghan soldier.
CNN's Matiullah Mati, Ivan Watson and Najib Sharifi contributed to this report.