Tueni was killed on Monday by a large car bomb in a Christian suburb of Beirut along with three other people in the third political assassination since former prime minister Rafiq al-Hariri was killed in February.
"Jebran Tueni did not die, Al-Nahar carries on," said the frontpage banner headline of Beirut's leading Arabic-language Al-Nahar newspaper, published by Tueni.
Tueni, 48, published fiery criticism of Syria and its role in Lebanon in weekly editorials splashed across the newspaper's front page.
Many Lebanese politicians blamed Syria for Tueni's killing but Damascus was quick to deny any involvement. The assassination, however, strained the domestic political scene where Syria still has powerful allies.
"Enough...," was the headline of Al-Bayrak daily.
Other newspapers were more blunt: "The Syrian security regime assassinates Jebran Tueni," Al-Mustaqbal paper headlined.
"We are facing a real state of war ... aiming at preventing the emergence of a [sovereign] state in Lebanon," Christian politician Samir Geagea told LBC television.
Samir Geagea: We are facing a
real state of war
"It is a war to eliminate Lebanon's nationalist figures..."
Five Shia Muslim ministers close to Syria suspended participation in the government after it voted on Monday night to seek a UN investigation into a series of assassinations that have rocked Lebanon over the past 14 months.
A sixth Christian minister loyal to pro-Syrian President Emile Lahoud also walked out of the session.
The Shia ministers, loyal to the Hizb Allah and Amal groups, opposed the call for a UN inquiry into the killing of Tueni and others, but were outvoted by ministers who campaigned with Tueni for Syria to withdraw its troops from Lebanon in April after 29 years.
The government also called on the United Nations to form a tribunal of an "international character" to try suspects in the killing of al-Hariri.
"In security matters there are calls for international investigators ... in the judiciary there are calls for an international tribunal, and in the economy we face similar pressure"
Lebanese Energy Minister
"In security matters there are calls for international investigators ... in the judiciary there are calls for an
international tribunal, and in the economy we face similar pressure," Energy Minister Mohammed Fneish, a Hizb Allah member, told the group's Al-Manar television.
"It is not much different from the days of the [French] mandate... What is next?"
Hundreds of people, including journalists, politicians, supporters and sympathisers flocked to a Greek Orthodox church in the mainly Christian Ashrafiyeh district of Beirut to present condolences to Tueni's family, led by his father Ghassan Tueni, a well respected former minister and diplomat.
Hours after Tueni's murder, a UN inquiry team said in an interim report that it had fresh evidence to reinforce earlier findings of Syrian involvement in al-Hariri's killing and that Damascus had hindered the investigation.
The report to the UN Security Council by German prosecutor Detlev Mehlis also said there were 19 suspects, whom it did not identify, including five Syrians questioned by investigators in Vienna this month.
The 15-member council weighs its response to Mehlis's report at a meeting later on Tuesday.
The Security Council and Kofi Annan, the UN Secretary-General, condemned Tueni's killing and said his killers had to be brought to justice.