ANKARA, Turkey (AP) -- Opposition figures in Turkey say they have faced threats, violence, arbitrary detentions, a lack of TV airtime and even sabotage in the campaign for a referendum on expanding the president's powers.
The complaints come even as Turkish President Recep Tayyip Erdogan himself has slammed European countries for not letting his ministers campaign on their soil for the April 16 vote on giving his office more power.
Erdogan kept up the criticism in an Istanbul speech on Sunday, denouncing the Netherlands and then singling out German Chancellor Angela Merkel.
"You are committing Nazi practices too," he said. "To whom? To my Turkish brothers and sisters in Germany."
Politicians campaigning against the constitutional changes proposed by the Turkish president also say the state of emergency in Turkey since a failed coup attempt in July prevents them from getting their message out ahead of the vote.
"Those who advocate for a 'no' vote are faced with a series of obstructions," said Utku Cakirozer, a former journalist who is now a lawmaker for the opposition Republican People's Party, or CHP.
While he, too, criticized moves by Germany and the Netherlands to stop Turkish ministers from campaigning to Turkish citizens abroad, Cakirozer said "our democracy bar has been lowered a great deal and needs to be raised rapidly."
At stake are changes that would usher in an executive presidential system, merging the powers of the prime minister and the president. Erdogan argues that a strong presidency will make Turkey better equipped to deal with economic and security challenges.
Critics say it would give Erdogan too much control and further erode the democratic separation of powers in the country.
With opinion polls suggesting the outcome of the tight race could be determined by yet-undecided voters, "no" campaigners say they face an uphill battle because Turkey's TV channels are either pro-government or refrain from broadcasts critical of the government for fear of reprisals.
Erdogan and members of the government have dominated the airwaves, holding twice-daily campaign speeches that are televised live in their entirety on all channels. Inauguration ceremonies and state-funded official trips also frequently turn into "yes" campaign events.
Meanwhile, the pro-government media largely ignore campaign rallies by the "no" camp. Even state-owned media, which is obliged to be neutral, cuts away early from speeches delivered by CHP leader Kemal Kilicdaroglu.
Ibrahim Kalin, Erdogan's spokesman, disputed claims of an uneven playing field, saying the opposition was allowed to campaign freely.
"Just because the president and the prime minister's rallies attract more numbers and it looks like only 'yes' campaigning, that's not true. It's a misperception," he told journalists last week.
The CHP says it has counted more than 100 incidents of obstructions to the "no" camp, ranging from physical assaults and death threats to detentions by police.
Sinan Ogan, a "no" campaigner who broke away from a nationalist party that backs Erdogan, was interrupted in mid-speech this month at a university in Istanbul by a man who ran on the stage and knocked down the podium, sparking scuffles in the hall.
"It's either our electricity cut (during rallies) or leaflets torn apart, or (the rally venue) is being restored at the last moment, or the podium is attacked, or there is an interruption attempt so that we cannot speak," he told The Associated Press. "And even if you do speak, no TV station will air it."
His political ally, Meral Aksener, was forced to hold a campaign event in the dark after the electricity at her venue in the city of Canakkale was cut off.
Erdogan, who called the Dutch and German governments Nazis and fascists for barring Turkish ministers from campaigning in those countries, has said those who oppose the constitutional changes include terrorists and coup-plotters.
"That is why I believe my citizens, my brothers, will vote 'yes,'" he said.
Turkey's state of emergency allows the government to rule by decree and to suppress demonstrations and gatherings. Some 41,000 people have been arrested and tens of thousands of others dismissed from public sector jobs for alleged links to the coup attempt or alleged ties to terror groups.
Those in jail include some 150 journalists and a dozen legislators from Turkey's pro-Kurdish party, which also opposes the constitutional changes.
A decree issued under the emergency powers has eliminated the High Electoral Board's ability to slap fines on TV stations that don't devote equal campaign time to opposing sides.
During a visit to Ankara last month, German Chancellor Angela Merkel called for election observers to be allowed to monitor the vote. European institutions have also expressed concerns over the campaign process, including the restrictions on the freedom of expression and the right to assembly.
"If a constitutional referendum must absolutely be held during a state of emergency, restrictions on political freedoms have to be lifted," the Venice Commission, a legal advisory body of the Strasbourg, France-based Council of Europe, said in a recent report. "If the restrictions may not be repealed, the constitutional referendum should be postponed until after the state of emergency."
The Sozcu newspaper, one of the few remaining outlets critical of the government, said in a front-page article Wednesday that what the Netherlands did was "wrong," but questioned what was going on at home.
"The country's system of governance is changing but those who say 'no' are given no space to breathe," it wrote.