[GALLERY id=3232 cat=news]

Thousands of mourners lined up at the presidential palace in Warsaw on Tuesday to pay their respects to Polish President Lech Kaczynski and his wife, Maria Kaczynska, as their bodies lie in state.

tp-mourners-kaczynski-cp-84

Mourners gather Tuesday in front of the presidential palace in Warsaw, where the bodies of Polish President Lech Kaczynski and his wife, Maria Kaczynska, are lying in state. ((Petr David Josek/Associated Press))

The president and his wife were among 96 people — including other Polish military, government and religious leaders — who died Saturday in a plane crash in western Russia. Investigators are pointing to human error as the cause.

Mourners knelt, prayed and cried before the first couple's closed coffins in the Columned Hall of the palace, where the president had appointed and dismissed governments. The line to get in stretched to more than a kilometre long, but the mourners were not deterred.

"We will wait as long as it takes," said Alicja Marszalek, a retired telephone operator waiting with a friend. "We want to pay homage to them because they were wonderful people. He was a modest man, very well educated, intelligent and kind."

Polish television broadcast live images of mourners walking by the coffins. Many were families with children, parents and grandparents. Each coffin was flanked by a pair of soldiers, standing crisp and stone-like.

mourners-kaczynski-cp-84771

Mourners kneel down in front of the coffins of Lech Kaczynski and Maria Kaczynska. ((Czarek Sokolowski/Associated Press))

A funeral for the couple has been scheduled for 2 p.m. local time (8 a.m. ET) Sunday at the 1,000-year-old cathedral, Stanislaw Kracik, the governor of Krakow province, said Tuesday.

Prime Minister Stephen Harper and U.S. President Barack Obama announced that they will attend the funeral.

Kaczynska's body was flown back to Poland from Russia on Tuesday morning, two days after her husband's was repatriated. Marta Kaczynska, the couple's only daughter, wept as she met the plane along with Jaroslaw Kaczynski, the twin brother of the late president.  

Crowds of mourners filled the streets of Warsaw to watch as the casket was ferried from the airport to the palace, where the two bodies are to lie in state for several days.

Poland's parliament held a special meeting to honour the memory of the couple and the legislators who perished in the crash.

Bronislaw Komorowski, the parliamentary speaker and Poland's acting president, told a Polish television channel that he hopes to announce an early election date Wednesday.

Crash investigation continues

Polish and Russian investigators are still trying to determine what caused the Tupolev Tu-154 to crash. The plane went down while trying to land in dense fog at Smolensk in western Russia, killing everyone on board.

Russian investigators have suggested human error may have been to blame for the deadly crash, saying Monday there were no technical problems with the Soviet-made plane. Russian media reports have also suggested that the Polish pilot may not have understood weather warnings from airport staff.

But a former Polish presidential pilot who has experience flying the Tu-154 told CBC News on Tuesday that the pilot involved in Saturday's crash was a skilled pilot who spoke Russian well and would have had no problems understanding instructions.

Investigators still aren't clear on why the plane tried to land in the foggy condition. Some people have speculated that passengers may have pressured the pilots to land, but Polish investigators said there's no evidence of this.

The government-owned plane was carrying dozens of military, government and religious leaders to a ceremony in memory of more than 20,000 Polish officers and intellectuals who were executed by Soviet secret police in the 1940 Katyn Forest massacre.

Officials are still working to recover and identify the bodies of the passengers. So far, 87 bodies have been recovered and 40 identified, Polish Prosecutor General Andrzej Seremet said.

With files from CBC News