Ukraine may get get access to blast site

Ukraine may get the access it has demanded to the site in the border area of southeastern Poland where a missile killed two people on Tuesday, Polish officials say.

Warsaw and its Western allies say evidence from the scene points to the explosion being caused by a Ukrainian air defence missile that went astray in pursuit of a Russian missile. Kyiv denies this, saying it has evidence of a "Russian trace" in the blast.

Polish President Andrzej Duda said on Wednesday that including Ukrainian officials in the investigation would require the agreement of both countries leading an ongoing investigation, Poland and the United States.

"If Ukrainian guests want to see the investigation, we will be able to show them, just as I have been shown," Duda said on Thursday during a visit to Przewodow, a village six kilometres from the Ukrainian border where the missile landed.

"When it comes to participating in the investigation and access to documents and information, this requires specific treaty provisions, international law provisions, international agreements."

Duda did not elaborate on whether Poland would grant such access.

"Ukraine and Poland will co-operate constructively and openly on the incident caused by Russian missile terror against Ukraine," Ukrainian Foreign Minister Dmytro Kuleba wrote on Twitter.

"Our experts are already in Poland. We expect them to swiftly get access to the site in co-operation with Polish law enforcement."

Duda said investigators found no sign of a second missile on Polish soil. Some initial media reports mentioned two rockets.

The explosion has stirred fear and disbelief among residents of Przewodow, a village of about 440 people, raising concerns among locals that the Ukraine conflict, Europe's most deadly since World War II, could spill across the border into NATO member Poland at any time.

Presidential adviser Jakub Kumoch earlier said that Poland had video evidence regarding the blast.

He said that from the missile debris, the depth of the crater and the amount of fuel used it was possible to calculate where it was fired from.

Kumoch did not provide any other details. He said that he wanted the Ukrainians to get acquainted with these materials first, in contact with those conducting the investigation.

Poland believes the missile was an S-300, an old Soviet-era rocket used by both Russia and Ukraine.

While Warsaw and Kyiv differ on the location the missile was fired from, they and other Western allies are united in the view that ultimately Russia is at fault.

"The Russian side must be aware of the threat it poses by bombing ... at a distance of literally several dozen kilometres from the Polish border, that any of the missiles, whether from the Russian side or those Ukrainian anti-missile systems, can land on the territory of a foreign state, in this case, Poland," said Adrian Kubicki, Poland's Consul General in New York.

"So nothing here changes the assessment that the Russian Federation is responsible for what happened."