This is a summary of Saturday's events regarding Ukraine, for the latest, please click here

Ukraine said it has shot down a Russian hypersonic missile over Kyiv using newly acquired US-made Patriot defense systems.

Ukrainian Air Force commander Mykola Oleshchuk announced the operation on Telegram on Saturday. He said that a Kinzhal-type ballistic missile was intercepted in an overnight attack on May 4.

"I congratulate the Ukrainian people on the historic event. Yes, we shot down the 'unique' Kinzhal," Oleshchuk wrote.

The unconfirmed claim would mark the first known case of Ukraine successfully intercepting what's seen as among Moscow's most modern missiles. Russia had previously boasted about the missile's speed and capability.

The Russian military say it has a range of up to 2000 kilometers (around 1,250 miles), with a speed 10 times that of sound. It is therefore difficult to intercept.

The US agreed to send its most advanced surface-to-air defense system, the Patriot, in October.

The missiles can target aircraft, cruise missiles and shorter-range ballistic missiles such as those Russia has used to bombard residential areas during the conflict, which is now in its 15th month.

Here are some of the other notable developments concerning the war in Ukraine on Saturday, May 6:

Russia says Ukraine and 'Western patrons' responsible for attack on writer

Russia's Foreign Ministry said late on Saturday that it held both Ukraine and its backers responsible for a car bombing in Nizhny Novgorod that reportedly injured Russian nationalist writer Zakhar Prilepin. 

"Responsibility for this and other terrorist acts lies not only with Ukrainian authorities, but also their Western patrons, the United States in the first instance," Russian news agencies quoted the ministry as saying. 

The statement said that Washington and other countries' failure to denounce the attack on a writer was "self-revealing." 

Russia has reported several attacks in recent days both inside its territory and around the long-occupied Ukrainian region of Crimea, most notably a foiled drone strike it described as an assassination attempt on President Vladimir Putin. 

Ukraine has generally either denied any part in such actions or sometimes insinuated that it might be domestic unrest within Russia. On Saturday, Ukraine's Ukrinform state news agency quoted the SBU security service as saying it could not comment on any alleged involvement. 

"Officially, we cannot confirm or deny the SBU's involvement in this or other explosions which occur with the occupiers or their henchmen." Ukrinform quoted the SBU as saying.

Ukraine and Russia swap prisoners, including soldiers who defended Mariupol

At least 45 captured fighters have returned home, Andriy Yermak, a top adviser to President Volodymyr Zelenskyy of Ukraine, said on Telegram.

The Ukrainian servicemen belong to the Azov regiment — a unit of the Ukrainian National Guard — a bulk of whom were deployed to defend Mariupol at the start of Russia's invasion.

"Excellent news on this sunny day. We are returning home 45 of our people. Thirty-five privates and sergeants, 10 officers," Yermak said.

The Russian Defense Ministry said in a statement they secured the release of three Russian pilots. They were being provided with medical and psychological assistance.

The ministry did not mention the Ukrainians who returned home during the prisoner swap.

Ukraine's military intelligence agency, which coordinates prisoner exchanges with Russia, did not mention the swap either.

Russia claims to have downed Ukrainian missile over Crimea

Russia claimed its forces downed a Ukrainian missile over the Crimean peninsula, with Russian-appointed Crimean governor Sergei Aksyonov saying there was no damage or casualties.

"Air defense forces shot down a ballistic missile over the Republic of Crimea. This missile was launched with Ukraine's Grom-2 system. There was no damage or casualties," Aksyonov said on social media.

Russia illegally annexed Crimea in early 2014, a move that most of the world denounced as illegal.

Russia's report came a few hours after Ukraine's assertion that its forces took out one of Russia's most advanced weapons using a US-made Patriot battery. 

Ukraine had repeatedly asked for the air defense system from Western allies and received them from the US, Germany and the Netherlands in April.

Moscow says nationalist author targeted in 'terrorist' bombing

Russian nationalist writer Zakhar Prilepin was injured in a bombing targeting his car in western Russia's Nizhny Novgorod city, Russian media reported. Moscow called the incident a "terrorist" attack, blaming Ukraine, the United States and the United Kingdom.

The author was wounded but conscious, Russia's TASS news agency said on Saturday. It added that preliminary information suggested the car was rigged with an explosive device at the bottom.

Another person was killed in the explosion, Russia's Interior Ministry said.

Russian Foreign Ministry spokeswoman Maria Zakharova accused the US and the UK of being responsible for the incident.

She said in a Telegram post that "Washington and the NATO have fostered another international terrorist cell: the Kyiv regime."

German court overturns Ukraine flags ban around Soviet monuments

A court in the German capital Berlin has overturned a police ban on Ukrainian flags around Soviet memorials on May 8 and 9, which mark the commemoration of the end of World War II.

German police announced on Friday a ban for the second year in a row on any Russian or Ukrainian flags and uniforms as well as George ribbons.

However, a Ukrainian organization challenged the order at court.

May 8 and May 9 mark the 78th anniversary of Germany's liberation from National Socialism. May 8 also marks Victory Day in Europe, when German forces surrendered to the Allies during World War II.

More DW coverage on Russia's war in Ukraine

Ukrainians living in the occupied east are being forced to take Russian citizenship — otherwise, they face deportation. Kyiv is sending mixed signals about what its citizens should do. 

Police confirmed a trip to Germany by Ukraine's President Volodymyr Zelenskyy this month. But such plans are usually kept under wraps. One German outlet now cites Kyiv as saying it's furious and considering its options.

rm, rmt/wd (AFP, AP, Reuters)