Poland"s attorney general is due in Moscow...

The Polish government Tu-154 crashed on the morning of April 10 while attempting to land in heavy fog at an airport near Smolensk. All 96 people on board were killed, including President Lech Kaczynski, his wife and dozens of top officials who were to participate in a memorial service for the victims of the 1940 Katyn massacre.

Spokesman Mateusz Martyniuk said the main purpose of Andrzej Seremet"s visit is "to get assurances that the investigation materials will be transmitted to Poland as soon as possible."

"Certainly, there will be discussions on the timing and mode of transmission of these materials," the spokesman said.

Russian and Polish investigators and experts are jointly investigating the causes of the deadly crash, while Polish military prosecutors are conducting their own investigations.

WARSAW, May 4 (RIA Novosti)