Al Jazeera's Imran Khan, reporting from Erbil, said it was not clear if the journalists were executed or killed during the crossfire.
"This is the first time that we are seeing an attack so brazen on such a civilian target," Khan said. "It's really a cause for concern here in Iraq."
Journalists have been under attack in Iraq over the last year. On Dec. 15, gunmen shot dead television presenter Nawras al-Nuaimi in northern Iraq.
Nuaimi, who worked for Al-Mosuliyah TV, was murdered as she was walking near her home in Mosul, about 310 miles northwest of Baghdad.
The latest attacks in Tikrit took the number of journalists killed in Iraq to 14 in less than three months.
Violence in the country has reached a level not seen since 2008, when the country was emerging from a period of brutal sectarian killings.
More than 6,650 people have been killed in Iraq since the beginning of the year, according to figures from news agency Agence France-Presse based on security and medical sources.