Locals fear pro-Russian separatists will unleash an assault on their city now that President Vladimir Putin has finished hosting world leaders to mark the Soviet triumph over Nazi Germany.
“Everyone’s talking about it,” said Iryna Hrynko, 40, a designer who arrived last year after fleeing the rebels’ Donetsk stronghold.
“Friends back home even tell me about an attack.”
Mariupol, an industrial hub of half a million people, sits on the fringe of Ukraine’s yearlong insurgency, which has killed more than 6,200 and ruined Russia’s ties with its Cold War foes.
An attack would bury the latest Minsk truce brokered by Russia and Germany and risk more sanctions for Putin’s government.
It could also reignite calls to arm Ukraine.
“If a new attack takes place, the Minsk agreements will be ultimately dead, and a new initiative at negotiating a lasting settlement -- in whatever format -- is unlikely for longer,” said Joerg Forbrig, senior program director at the German Marshall Fund in Berlin.
“The U.S. and several European Union countries will see a renewed debate on lethal arms supplies.”
Sitting just 25 kilometers (17 miles) from rebel positions, between Russia and the Crimean peninsula Putin annexed last March, locals see reasons to be scared.
On Mariupol’s outskirts, shelling is frequently heard from the nearby town of Shyrokyne, where fighting is continuing.
Military personnel flood the city, building defensive positions and bunkers and blocking approach roads with huge concrete blocks.
Visitors arriving by bus must clear multiple checkpoints where searches can take hours.
While Russia blames Ukraine for breaking the truce, U.S. Defense Secretary Ashton Carter told lawmakers last week that the separatists may be readying a new offensive.
Russia has built up forces around and inside Ukraine, and has the capacity to attack “with very little warning,” NATO Secretary General Jens Stoltenberg said Monday.
International monitors warn an attempt to take Mariupol risks “disastrous consequences” for diplomacy.
To prepare for the worst, Ukraine’s army is giving classes at schools and universities and taking people on training drills, said Dmytro Horbunov, a military spokesman in Mariupol.
“We have enough people to defend the city,” he said, citing the presence of thousands of troops.
“Fortifications are built day and night. The front line is completely improved.”
In Moscow, there’s no sign of an imminent assault.
Putin welcomed leaders from Zimbabwe’s Robert Mugabe to Germany’s Angela Merkel at the weekend, training the global media glare on the Russian capital.
He’s shown leniency before such showcase events in the past.
In the run-up to last year’s Sochi Winter Olympics, he pardoned jailed billionaire opponent Mikhail Khodorkovsky and freed members of punk bank Pussy Riot.
Days after the Games ended, Russian forces seized Crimea.
The Donetsk rebels will eventually seize Mariupol, according to their leader Alexander Zakharchenko.
“It’s easy to outflank it and they’ll surrender,” he said in April.
“Don’t forget, our mothers and sisters live there.”
President Petro Poroshenko has said the rebels may attack this month, threatening martial law.
An assault would probably bring stiffer EU and U.S. penalties for Russia, which denies involvement in the conflict.
Russia’s economy is entering a recession, while the ruble is down by a third in the past year.
If the truce isn’t met “and there are crass violations -- as in Mariupol -- then we’ll have to speak about further sanctions,” Merkel said March 16.
Some in Mariupol are no longer panicking after warnings of an offensive that hasn’t arrived, according to Roman Sokolov, a sailor turned entrepreneur who heads Mariupol Defense, which raises cash for army hospitals and holds pro-Ukrainian events.
While Sokolov’s group draws volunteers from the 1 million people who’ve been displaced by the fighting, pro-Russian and pro-separatist sentiment is strong in Mariupol.
Older people, particularly pensioners, oppose the government.
For now, billboards carry patriotic messages adorned in the-blue-and-yellow national flag.
And there’s no shortage of helpers to prepare for the worst.
“Local businessmen, military personnel, volunteers and displaced people handle Mariupol’s defense,” said Hrynko, the designer.
“They understand what they’ll lose if the rebels come here. The rest watch indifferently, waiting for Putin.”