Special Tribunal for Lebanon spokesman Marten Youssef said that several sessions will be held in June between the prosecution and the defense offices, reported An Nahar on Tuesday.

In the past five months the tribunal witnessed excessive activity, Youssef told the daily.

The Special Tribunal for Lebanon Trial Chamber has scheduled a hearing on June 13 to hear arguments on the jurisdiction of the STL and the legality of its creation, announced the tribunal in statement on Monday.

“The defense counsel representing the four accused - Salim Ayyash, Mustafa Badreddine, Hussein Oneissi, and Assad Sabra - filed motions recently challenging the legality and jurisdiction of the tribunal,” it said.

Herman von Hebel, Registrar of the Special Tribunal for Lebanon, has designated one lead counsel and two co-counsel to represent the victims of the February 14, 2005 attack in the Ayyash et al. proceedings, the court said in a statement on Wednesday.

Pre-Trial Judge Daniel Fransen decided on May 8 to grant 58 people the right to participate as victims in the proceedings as one group.

The defense team for Mustafa Badreddine -- who is accused of involvement in the 2005 assassination of ex-PM Rafik Hariri -- on Friday filed a motion challenging the legality of the establishment of the U.N.-backed Special Tribunal for Lebanon which has been probing the case since 2007, the STL said in a statement.

“In its Motion the Badreddine team argue that the STL was unlawfully established and that the Security Council abused its powers by adopting resolution 1757 (2007),” said the STL.

Deans and professors of a number of Lebanese universities have concluded a visit to the Special Tribunal for Lebanon, announced the STL in a statement on Wednesday.

The visit, which lasted from 7 to 9 May, included discussions with STL President Judge Sir David Baragwanath, as well as other senior tribunal officials.

Defense lawyers before the U.N.-backed court probing former Lebanese premier Rafik Hariri's murder sought Wednesday to have the tribunal's creation declared illegal and unfit to judge their clients.

Lawyers for Salim Ayyash -- one of four men wanted for trial in connection with Hariri's car bomb death in 2005 -- asked "the trial chamber to find that the establishment of the court was not legal."

Special Tribunal for Lebanon Pre-Trial Judge Daniel Fransen has determined that 58 of the 73 victims of the February 14, 2005 attack who applied to do so can now participate in the Ayyash et al. proceedings, announced the STL in a statement on Wednesday.

“Fransen has reviewed the 73 victim applications he has received, 15 of which were deemed to be incomplete,” it added.

Special Tribunal for Lebanon spokesman Marten Youssef said on Tuesday that the defense office can contradict the claims of the prosecution in 2012, stressing that the Lebanese authorities are obliged to cooperate with the lawyers.

Youssef revealed in an interview with the Kuwaiti al-Seyassah newspaper, that the prosecutor’s office provided the defense office with 28,000 pages on the investigations in ex-Premier Rafik Hariri’s murder and related crimes.

The trial of four Hizbullah members indicted in ex-Premier Rafik Hariri’s Feb. 2005 assassination will be held late 2012 or early next year, Special Tribunal for Lebanon sources told the Kuwaiti daily al-Rai on Monday.

“The trial of the accused in former PM Rafik Hariri’s murder whether in their presence or in absentia will start between the end of this year and March of next year,” the sources said.

The defense team of Hizbullah suspect Mustafa Badreddine challenged the jurisdiction of the Special Tribunal for Lebanon by submitting a preliminary motion, al-Akhbar daily reported Saturday.

The move came on Friday before the May 4 deadline set by Pre-Trial Judge Daniel Fransen to file motions challenging the tribunal's jurisdiction, it said.